Transmission Fluid - really that hard? - Page 3 - 986 Forum - The Community for Porsche Boxster & Cayman Owners

I've read just about every post on this forum and others about recommendations for Transmission Fluid. Here are the two take aways for my 2000 Boxster S: 1) Correct oil for this is a GL-4 75W90. 2) Using a GL-5 in this transmission is BAD and will wear the yellow bits. 3) But, everyone uses a GL-5 (Swepco, Redline, Mobile1, etc) because that seems to be all that is available. This feels very incongruent. What, pray tell, am I missing?

I just went through the same thing, I am getting ready to change the oil in my 2000 Boxster S transaxle. I was all fired up to buy the Porsche fluid until I saw the price compared to other 75W90 gear oils... I have a couple of gallons of Mobile Delvac 75W90 because I just did the diffs and t-case on my Toyota FJ Cruiser and I had bought extra to do the diffs on my old Tacomas. I wondered if the Delvac would be good for the Boxster, searched and read some threads (some folks have had good results with it), and then just ended up buying 3 liters of the Porsche Transmission Oil. Out of the places I checked, I found the best price at ECSTuning for right at $30 a liter: 2000 Porsche Boxster Roadster S H6 3.2L Drivetrain Manual Transmission ES#1513799 75W-90 Gear Oil Manual Transmission Fluid - 1 Liter - 99991754600 Suncoast was a little higher at around $39. I had to buy a few other odds and ends from them too and shipping was only around $9 so it wasn't so bad. I would have been tempted to try some of the others, but I already have all the issues that I have seen described when using non-oem gear oil (hard shifting when cold, etc) and I didn't want to make it any worse. (I'm not sure what's in there now, I am at 108,000 and I have service records going back 50k miles and I don't see a transaxle oil change so I figure it is time). Too many folks that I respect say to stick with the Porsche oil for this one so I decided to play it safe. I will report back once I get it changed; I am taking some time off around Christmas so hopefully I will get to it soon. Steve Edit: on my son's 95 Miata we used Redline MT-90 because it was almost impossible to find a true GL4 75W90 and we (he) loves it. I thought that was expensive at ~$15 a quart... until I saw the Porsche gear oil... Some places had it at over $50 a liter

I think with redline gl-5 you use the 75w90 'ns' formulation, where ns is non-slip or somesuch - no friction modifiers so that the syncros work ok.

Quotes source post: 377190

Everything. Porsche uses a unique gear oil (it has no Gl rating) that is manufactured for them by an obscure branch of Royal Dutch Shell. When we questioned several manufacture's about their products for this application, the larger and apparently more honest ones (Mobil, Castrol, etc.) stated that it is an unusual product with unique specs, and that they had nothing comparable to offer because of the small market. The smaller "blenders" all claimed to have the perfect match for it; only problem was that their "matches" caused noise, hard shifting and other problems, which promptly went away when their products were drained out and replaced with Porsche's OEM fluid, which is also a full synthetic. It's your car and you money, we only use the OEM product.

Quotes source post: 377204

In my opinion we are lucky to have JFP and other folks like him on the forum. For me it is about trust and faith. (And Porsche doesn't always get it right, but they mostly do or else we would not love the cars the way we do) I replaced my IMS with the LN because I wanted to not worry about it. $90 for Porsche fluid vs $45 for 3 quarts of aftermarket isn't that big of a difference in the grand scheme of things. The peace of mind for doing it right is worth more to me than the extra $45-$50. And if I try one of the others and don't like it then I am out the $45 + the $90 for the oem fluid and two afternoons of grunting under the car pumping my little pump, leaking oil all over the place, etc... After changing 2 diffs and a t-case on the fj, with two more diffs and one manual transmission on the tacomas, I am worn out from the pumping. (ok that sounds bad..) I would hate to have to do it twice Steve

Spoke to Pelican and Pedro about this - funny, Pedro and the owner of Pelican Parts both use the Swepco 201 in their boxsters. But, as Steve and JFP say, for ~$50, is it really worth it? I'm sure I'd be fine with a different product, but I think I'll stick with the stock replacement as well...

I just found this bulletin: http://bethnrayndogs.com/car_docs/Porsche/porsche/Porsche_Tech/Porsche_TECHNICAL_BOOKS/Tech_Bulletins/Gp3_4a-99-1eps.pdf The Shell 999 917 546 00 seems to be the Porsche Oil, at least the part number matches. The others are all in 20 liter sizes Doing a search for Shell 99991754600 leads me to a lot of threads, but no places to buy. For the amount of time I have spent researching this I have probably used up any savings from doing the job myself Steve

Ok found another thread that seems to say that Audi uses the same transmission oil, for $20 a liter: Audi Parts - Audi Parts | Audi Wholesale Parts | Audi Accessories | Cheap | Discount Audi Parts Thread: Rennlist Discussion Forums - View Single Post - Right gear oil for GT3? Anybody want to try this out and report back Steve

Lots and lots of race teams, and the guys over at Gbox use the Delvac 75W90, which is what I have in my 996 box at the moment (which also has a Guard LSD in it) and I'm plenty happy with it. I've run the Delvac stuff for years in multiple Porsche boxes. If you go this route, you have to buy in the gallon, NOT the quart (like you find at the local Autozone), as apparently they are grossly different fluids. Supposedly, the "new" Audi manual trans fluid (what comes in, say, a new S5) is the cat's meow, but it's something like $60/quart from your dealer!!!

Quotes source post: 377236

Interesting, as we just put a Gbox overhauled six speed back into a 996TT, and the paperwork that came with it said to use the OEM fluid only ..............

Quotes source post: 377243

That is interesting.. as the last time I needed fluid, I drove out to Gbox and they just pumped me 4 quarts of Delvac out of their drum.....

Quotes source post: 377530

Perhaps it had something to do with the type of LSD you had installed, but their recommendation for every rebuild they have done for us is the OEM fluid only.

Quotes source post: 377532

Perhaps. I am running a Guard LSD in mine (though the next time around I'm going to do the OS Giken, as Guard hasn't exactly gone in the right direction since the sale of the company).

Following up to this thread, I replaced my MT Oil in my 2000S last week with the Porsche Fluid. I have immediately noticed the following things (albeit after only 2 test drives of about 40 miles) 1. Before - whenever I would park, I would always go ahead and put it in reverse for next time, otherwise I would have a devil of a time getting it into reverse when it was cold. 2. Before, when I would first start up for the day and drive off, I would have a devil of a time going from 2nd to 3rd until it had sufficiently warmed up. Both of these are resolved with the new Porsche MT Oil, and overall shifting is much smoother. I am not sure what was in there before or how long it was in there, but I am loving the new fluid very much, definitely worth it to me. Steve

When I drained my transmission, I replaced with Amsoil 75w-90. No noticeable difference, or if so slim to none. Did not improve or worsen shifting conditions or noise.

GL-4: Red Line Synthetic Oil - Gear Oil for Manual Transmissions - MT-90 75W90 GL-4 Gear Oil

Quotes source post: 379786

Just bought a 2001 Boxster S with 118,000 miles. When cold it is very slow to go into any gear. About 3 miles later it is ok. I did a drain and fill with Porsche fluid - no change. I do not know if it was ever changed before. In my BMWs, I always used Redline in the trans and diff. BMW specs a lighter gear lube than Porsche, but I was hoping that a lighter fluid would make it easier to shift when cold. Anyone successfully using Redline and which viscosity? Thanks.

Quotes source post: 443022

So I think that I can add some help to this thread. The oil debate seems to NEVER end, and that is due in part I think to the fact that most shops have a oil of choice. So here is the reality with regard to the 986 gearbox. The reason that companies like Gbox and others put a disclaimer to use only Porsche OEM fluids, is for their protection. Some synthetic oils do not work well inside these gearboxes as they are simply too slick to allow the synchronizers to work at their optimum ability. As such, I myself do not recommend them. I know however that there are any number of shops that use them all the time. The Porsche oil is quite expensive and not easy to find. There are several other oils out there that will do the job just fine, but will have their own unique characteristics. One of them will be that shifting will be stiffer when the gearbox is cold. This is NOT a bad thing. You want oil to adequately coat the synchronizers, and gears to protect them when they first start running together. Going to a lighter fluid to remedy this cold start up feel, is not a good idea. In making the shifting slightly easier you are also wearing the internals, especially the synchronizers, more quickly. This will also result in a earlier rebuild time. So on and on the debate goes on. Here is what most every rebuilder, at the end of the day is going to say, unless they have some oil they use on everything. Pretty much any 90 weight non synthetic oil will be just fine for your gearbox. You can spend the money on the OEM oil, which experience has shown one to work better than the other in terms of what they recommend. (get the shell oil if you can find it) Or you can certainly use a wide variety of others. Just keep in mind that synthetics CAN wear some parts prematurely, even if they are also protecting others. As I mentioned, many shops have a favorite oil, usually one that has shown itself to work in a wide array of gearboxes. For me, I tend to recommend the Swepco 201 for the street and the 210 for the track. There are other blends that I think some people have had issues with, but these two, as far as I know have never caused any issues in any Porsche gearbox. I hope that this is somewhat helpful. Feel free to give me a call with any more specific questions. I am always around to help. Erik Johnson [phone removed] phone

http://986forum.com/forums/437747-post24.html http://986forum.com/forums/437794-post26.html http://986forum.com/forums/437800-post28.html

Erik, compelling argument about the cold starts. I will stick with the heavier fluid. Thank you!

Quotes source post: 381021

I'm with this guys, except that I blend 2 quarts of Red Line MT-90 with 1 quart of Red Line NS (Non-slip). Otherwise it is too slippery for my limited slip diff. to work well.

My transaxle is a stock 6 sp. Do I have limited slip?

Quotes source post: 443223

If it is a stock 6 speed then you do not have a limited slip differential. Our differential and transmission are combined as a "transaxle" and the differential and transmission share the same oil.

Quotes source post: 443233

This is what makes it such a difficult application. Most of the GL-5 oils that are great for differentials are corrosive to copper, and destroy the synchros. The Porsche OEM stuff is quite good for this unique application, but my local dealer only buys it in 55 gal drums, and would not order me any. The Red Line MT-90 is also very good, and synchro friendly. If you add in a Torsen type limited slip, it is just too slippery without blending.

Quotes source post: 381021

This what I use in my fake Diablo...Audi V8 w/ an Audi O1E 6sp transaxle from about 2006...the trans is Getrag and almost identical to that of a Boxster...but supposedly way stronger. Seems to work fine.

Hi all, I just want to share my experience. I bought my 2000S last year and a couple of months ago I changed the transmission oil to play safe and because the shifting was hard, it had a small leak too, I bougt "Total Dual 9 FE 75W-90" and after the first drive I started hearing a quick quick noise in Neutral which disappears immediately when I press the clutch or in gear and after some minutes of drive it also dissapears, the shifting improved but the little oil leak increased too... I guess the oil was never changed (115.000kms) as it was quite dark with high viscosity. Now I'm trying to get swepco 201 (general 80W-90) or Swepco 202 (75W-90 the better version as I checked on Swepco web page...) I'm waiting for a local dealer to give me a budget for the arms seal and the IMS replacement (three weeks waiting already) but I'm thinking in chainging the transmission oil myself again just to stop the noise and any probable problem in the meanwhile. Any suggestions on the oil? shell Shelix Spirax S6 ADME 75w-90

Quotes source post: 631681

Use the factory oil.

Quotes source post: 631683

+1 on using the Porsche 6 speed trans oil I went through what you are going through and JFP is right on. It’s expensive but it is the only one that worked for me.

Oil is cheap, transmissions are expensive. You bought a freaking Porsche. Just invest in the Porsche oil. In all the time you have been trolling forums and researching formulations and tracking down which Shell formula matches the “secret” Porsche fluid, you could have just bought the Porsche fluid and changed your oil, and attended three track day events or driven to the Rocky Mountains and had a great vacation. Get busy livin’. Or buy a Honda and save money. Maybe you just bought the wrong car for your budget.

Hey 10, don't be a dick. There's nothing wrong with saving cash, and if there's a good alternative then most would argue that it's silly to say "ooooh I only use the best porsche products for my 20year old car that's worth $10k" OP, the issue with most gear oils is that they weren't designed for the setup in our transmissions, which use soft yellow metals (bronze) and in a hypoid arrangement. Royal purple makes one specifically for this type of application and that's what I plan on using during my next oil change, purely because I can have it delivered to my house and not have to drive 3 hours to the closest dealer to buy the factory oil. Some say it works well, others disagree. I don't doubt that the factory is the best (they don't even make the stuff, btw), but the idea that porsche has everything figured out and they know the secret ingredients to make perfect products is crazy. Oh, and to the post about transmissions being expensive, I hate to break it to you but the 5 speed transmission, better known as an 01a, is considered to be a throw away piece but a lot of euro spec racers and can be harvested off any fwd a4 for a few hundred dollars. But wait, do the audis use porsche transmission oil? Oh damn, what a mess this is........ Sent from my POCOPHONE F1 using Tapatalk

Hello Ike84, Luke at Sunset Porsche will sell you and ship the correct gearbox oil to your door.. Good luck!

Quotes source post: 631832

Hey thanks gilles! I wasn't able to find anyone who would ship it. I appreciate the heads up. Sent from my POCOPHONE F1 using Tapatalk

Just bought this. I'll be changing it soon. 2001 base with 54,000 miles. I believe it's the best way to go. I'll never have to change it again.

Well original oil then it will be... unfortunately i don't live in the US, therefore price is ridiculously expensive that's why I try to save. Enviado desde mi SM-A505G mediante Tapatalk

.....if I am harsh. But it’s a freaking expensive and exotic German sports car. Just because it has depreciated and is twenty years old and kids are buying them for $5,999, doesn’t change the fact that it’s a highly strung thoroughbred that requires proper maintenance. If you can’t afford the care and feeding, then you should not buy the machine. Would you search for cheap oil for your Lear Jet because it’s twenty years old? These things are more expensive to maintain than a Honda S2000. We need to hit people between the eyes with a 2x4 and save them from themselves. How many heartbreak stories do we have to endure, year after year after year, from these new people buying these cars because they are cheap and trying to get by on the cheap, and end up losing thousands of dollars due to their poor decisions and leave the world with more old, used up Boxsters and more horror stories that scare people away from the joys of Porsche ownership? I will always sound harsh on this forum as this format has no tone. But better we educate folks about the realities of owning these machines than continue to perpetuate this fantasy that you can buy a Boxster and keep her running for pennies on the dollar. That is a fallacy that will only end in heartbreak and broken transmissions and another abandoned mid-engined beauty in the crusher instead of providing a great driving experience to a future generation. Now, pardon me as I sign off and go for a drive. Cheers.

Quotes source post: 631827

10/10ths gave me the same hard time when I was using the same crush ring, time after time, on motor oil changes. (Me doing so NOT because I was too cheap to buy a new one…but because it was inconvenient, I happened not to think of it, whatever…and I’d done oil changes time after time after time using the same crush ring, with no negative consequences.) 78F350 was even MORE disgusted with that practice! We differed on that, in a friendly give-take kind of way. Nobody even suggested anyone was being "a dick." And here? I totally agree with his logic. Transmission oil changes? It’s not like an oil change. You’re not doing them every year. We’re not talking about a major investment here. As JFP says, “Use the factory oil.” Got mine by the quart from Sunset Porsche. Easy-peasy, and really not that pricey.

Ike... 10's most recent post is spot on. I recognized no "dick" except your move suggesting he was a dick. You bought a Porsche to save money? lol. Get a Honda.

I have to agree with 10/10ths as well. When people ask me about buying a Boxster I ask if they are handy or can afford to spend thousands on repairs at a shop. This is not a car for so many people. My budget for a Boxster was $20K. I bought a $12K car so I'd have $8K for repairs/maint. And that's doing all of the work myself. I can't even imagine what it would have cost if I sent my car to a shop. A cheap Porsche is the most expensive car you'll ever own.

I'm in no way disagreeing with what 10 said, it's how he said it that I took issue with. "Maybe you bought a car outside your budget" That's a rather condescending comment to make. "Get a honda" Not any better. The forum is supposed to be a place to share knowledge and to offer advice, not to make comments about people's cash flow or status in life. Too many of these posts wind up with this condescending elitism bull**************** about how great porsche is, how we love to spend money on these cars, and those of us who don't should be ashamed of ourselves. But it's cool, I have no right to tell anyone how to be happy, so if that's what you cling to then good for you. But I will say it over and over again as long as I am active here - these are just cars, have fun with them, and don't be a dick to people for asking questions. Sent from my POCOPHONE F1 using Tapatalk

Quotes source post: 631927

Sorry, but a good case could be made supporting the position that his comments weren't condescending at all. Only realistic and, in that sense, helpful to all, regardless of one's "cash flow or status in life." He was simply pointing out that buying an older Porsche for the seemingly bargain price of under $10K shouldn't lead one to the conclusion that it's all going to be smooth sailing, financially, once the title's in hand. Just because those comments were made with conviction doesn't make them irrelevant or nasty. Or "elitist." The forum IS a place to share knowledge and offer advice, in a considered, thoughtful and forthright way. Without casting aspersions. "10" could have said, "Maybe you bought a car outside your budget you dick" "Hey, dickhead, get a honda" But he didn't. You see the difference? In that case, he would be rightly condemned as stepping outside what's considered seemly and acceptable within a forum like this. But he didn't do that. You did. More than once. You should have led with "The forum is supposed to be a place to share knowledge and to offer advice, not to make comments about people's cash flow or status in life," NOT "Hey 10, don't be a dick." See the difference? The former makes a valid point, the latter just creates pointless acrimony. Help us all make this a friendly place. Buy whatever rotgut transmission fluid you like, mix and match various weights and brands to come up with the "magical combination" that makes for peerless shifting. But do so knowing that, just maybe, you're doing so against the advice of those who have learned from experience and know better.

....and for what it’s worth, I never bought that Ferrari 308 when they were JUST affordable to me a decade ago because I knew I couldn’t afford the timing belt service and all the other “Ferrari” taxes. If you met me, you would know I am as far from “Elite” as a janitor at Trump Tower. �� Seriously, though, a 1993 Miata was my only car for over 20 years. I scrimped and saved and bought the best quality, best maintained 986 I could find. I have a great local technician and I can turn a mean wrench myself. I grew up in the “Fast & The Furious” days and “Sport Compact Car” magazine. I WAS that “Rice Boy” kid. I’m just trying to use whatever old man wisdom I have accumulated over my years to help my fellow forum members. Hopefully my past mistakes can prevent others from suffering the same heartbreaks I brought upon myself. Just trying to help this awesome collective. And I’m sorry if my crush washer post sounded harsh, as well. Cheers, everyone. Now go out and drive your Boxster.

Ike, you've got a sympathetic ear here, with me. There are lots of people who won't see this post because they've used the "block user" function. You sound just like me about there being nothing magical (or even particularly unique) about the innards of the Porsche 986. BUT: I read this thread and to me, it looks like you took offense where none was intended. You must remember that for many owners, this car represents a culmination of a dream, and part of that dream is their obsession with OEM-Only, Factory-authorized, laminate-all-the-receipts-and-keep-them-in-a-binder sort of, for lack of a better word; worship. That ain't you, and it ain't me, but there's lots of room for people to love the car in lots of different ways. As with any forum (or any group of people) the answers you get will vary across the spectrum created by the variances of life's experiences. Yeah, now I'm preaching. sorry.... I'm a Mormon, hahaha. So, in all reality, 10/10ths is sorta on the money here. Many have tried other lubes and come back with horror stories; to the extent that most have determined that it isn't worth the risk to do otherwise. On my street-986 S, I used the OEM stuff from Suncoast. (But on the Spec Boxster, I didn't. that might tell you where my head is) Enjoy this forum for the diversity found herein. Try to be a lover, not a fighter. otherwise, everyone will block you, like they have me. :dance:

Quotes source post: 631949

Sorry for overreacting. My life experiences have taught me uniformly that mean people suck and I have a soft spot for the guy on the other end because usually there's no one to stand up for them. I tend to epitomize the "carry a big stick" philosophy lol. Anyway, cheers to the knowledge base. As pedro would say, happy boxstering! Sent from my POCOPHONE F1 using Tapatalk

Quotes source posts: 631949, 631955

Maytag ! You really think you’ve been all that blocked?? I can’t imagine that—you offer some of the most sage advice I’ve read on this forum. Well, if you are much blocked at least I feel in good company, though I suspect I’m more blocked than you. (This whole discussion kinda puts me in mind of that “I’m rednecker than you” country song.) I can’t figure out the mentality of “blocking” someone—why would you not just NOT read their posts if you so inclined. They're incapable of just skipping over those posters they don't want to read?? And it’s not like they succeed at a “I’ll show that guy!” by blocking—we don’t even know we’ve been blocked, or by whom. Whatever.. Aw hell 10 , don’t worry about the crush ring discussion. I’ve been worked over worse than that on quite a few occasions. I usually have it coming. And I learned something important reading through that thread. (I never knew the LN magnetic plug was supposed to be torqued so much more gently compared to the OEM plug. I guess I just got lucky—time after time I’d crank away on the thing when replacing it, torqueing it to roughly the same level as I would the original. I had NO idea they could be stripped out as shown in pics on this thread. As you say: "Cheers!" And “go out and drive your Boxster.” It’s always hard to know exactly when winter’s over around here. But it’s almost 60 out there at the moment—I’m actually pretty much ready to break her out of her long hibernation about now! :dance:

Quotes source post: 631976

You too, Ike .

Just called my Porsche dealer. They don't sell GL4 anymore. They can get GL5. I note on Pelican it seems to say the same thing. But the guy at Porsche is saying this is what Porsche suggests now. Is this true? Or is it just the only thing they have, so they suggest it?

GL4 and GL5 gear oils are NOT the same; some OEM's spec GL4 because it is friendly with brass/bronze alloy yellow metal synchro rings used in their trans, a GL5 gear oil contains additives the chemically attack and can destroy those synchro's.

Bit of a supposition here but applicable. As someone mentioned Honda, I've had a 97 Boxster and 97 Civic at the same time, had the same issue with transmission fluid/additives as I do with my boat. Not all 75W-90 oils are the same of course...many people on Hondaland with the 5-speeds heard that you can "cure grinds" with this miracle fluid called GM Synchromesh, which on the bottle, doesn't list its viscosity. These people read it online while nobody reported back after using it for a year, and here's why: Its for a Corvette transmission is suppose to have additives for an LSD. Thus people with Honda transaxles with an OEM style auto-torque biasing style (the ten gears) LSD will try it, and it will cure grinds for maybe 6 months. Then, you get a lovely noisy sound. This is because Honda's m/t fluids are a 10W-30 oil, considerably thinner than what the 986 or even corvette uses (or most transmissions actually), and there is an input shaft bearing that never gets any oil up there to its seal, same reason we have the IMS problem. Honda recommends their own fluid, but you CAN use 10W30 oil in its place for a short time (so says their service manual), and in my opinion, Honda makes among the most durable manual transmissions on any road car, hands down. But thus are the 'additives', as Honda uses its gear where the synchro touches as a deliberate wear point that is solid iron, its m/t boxes use a magnet as a filter (their automatics do this too, the drainbolt has a magnet you wipe clean). Back to the 986 tranny. Same issue, as you mentioned, the chemicals blended into it are meant for the metal the bearings are made with, such as copper and Zinc. Similar issue on my boat. I have a 1997 boat engine which is a chevy small block and the rockers are not rollers, meaning they rotate and was recommended to use oil heavy in zinc (25W-40). Because the year after this used roller rockers, you do not need to use this older oil and thus is recommended a GL-rated flud too. Due to new laws requiring boats to have cat converters, they would rather you not use so much zinc in this boat oil as the older oil is not catalyst friendly. I then must make a bit of a cocktail here as well, wanting the correct viscosity, but also wanting all that lovely zinc for my old-ass spinners. I therefore use Rotella T5 15w40, not the correct viscosity i wanted, but its said to have lots of zinc, and then ill add one quart of 25w40, because the zinc-filled oil is not around. Hope this side-trip helped someone to understand and research the stuff they put into gear oils and that if you change a type of bearing or component to a different material, you may need to change oils to ones with other kinds of additives. Edit: a lot of these viscosities changing or disappearing are usually due to more new laws against certain chemicals, so blame the lawmakers, not the dealership.