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YOUR RESEARCHManual Transmission Fluid?
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Combined work: Replace of the transmissions they sold and it worked + Use ac delco syncromesh in mine
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I used AC Delco Syncromesh in mine, It's not Porsche approved, but I have had luck with it in every manual vehicle I have owned. It was developed as a GM product with a special friction modifier for a GM truck transmission to save them from replacing all of the transmissions they sold and it worked.
Leading evidence: 'Combined work: Replace of the transmissions they sold and it worked + Use ac delco syncromesh in mine' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check their website' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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When I got the car I changed all the fluids, I put Lubromoly in the tranny which helped but not significantly.
Replace of the transmissions they sold and it worked
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Performed · outcome unconfirmed
It was developed as a GM product with a special friction modifier for a GM truck transmission to save them from replacing all of the transmissions they sold and it worked.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
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Performed · outcome unconfirmed
I used AC Delco Syncromesh in mine, It's not Porsche approved, but I have had luck with it in every manual vehicle I have owned.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
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Combined work: Replace of the transmissions they sold and it worked + Use ac delco syncromesh in mine
No successful repair reported for this finding.
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Reported fixes
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Read evidence and context
Discussions that performed work without a confirmed outcome
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Performed · outcome unconfirmed
I used AC Delco Syncromesh in mine, It's not Porsche approved, but I have had luck with it in every manual vehicle I have owned. It was developed as a GM product with a special friction modifier for a GM truck transmission to save them from replacing all of the transmissions they sold and it worked.
Replace of the transmissions they sold and it worked
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
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0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed
It was developed as a GM product with a special friction modifier for a GM truck transmission to save them from replacing all of the transmissions they sold and it worked.
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Hello expert peoples.
I did a search and I'm sure I have missed it, but the last post I could find was a few years ago so I thought I would check in.
What transmission fluid should I use? I have a garage queen that I will track 2-3 times a year
I saw references to Swepco, Amsoil, Mobil 1, Lubro moly. Cost is always a factor. Any consensus?
Thanks!
Porsche fill is by Shell and great for street cars but not really up to the job for track environments especially if you're not running a trans cooler. Any of the manufactures lieted above will handle the heat better than Shell but if you have an LSD then you want one of the ones speciofied for LSD's as they won't have any friction modifiers added to them. You also should run the thicker oils like 75-140 especially if you're not using a cooler a they protect better. I think they're all around $25. a qt. or liter. I use LE's Synolec 9920 as does Viking who runs many P-race cars down there near you somewhere.....
Thanks so much for mentioning the LSD. The 40th AE apparently has LSD whereas most 996's don't unless you have a GT2/GT3.
I found LE, and Motul looks like it is sold about 15miles from me. I will call them next week.
Thanks guys!
The reality is we don't really know so why take a chance when there's better products available. He's in Texas where it gets pretty damn hot on the track in summer/fall. Why not increase your protection with a product more suited to that environment. They all cost the same (+/-)....
To OP: Look atr Redline's 75-140 too....
The same can be said for taking a chance that some fluid that so far has held up in just a handful of cars for a few owners will not only hold up for a few track sessions per year for this owner but in the day to day life of a transmission.
They all sound so good when you read about them and the reviews. I found this Motul below on Redline Speedworx website for $15/liter. I see it at $25 to $35 on other sites so may pull the trigger. Any issues with this choice?
MOTUL GEAR COMPETITION FF 75W140
100% synthetic racing lubricant based on Ester-Technology For all hypoid differentials with limited slip system, gearbox with integrated limited slip differential, mechanical transmission, synchronised or not synchronised gearboxes, transfer gearboxes
Hey Krazyk! I agree it's been chilly but I am more worried about my first DE in April. I can wait until closer to the DE to change the fluid but as you know, it could be 90 in April with our crazy weather. At $15 I would rather take the better safe than sorry approach.
I just wanted to see if anyone has used the one I picked and had positive results.
I can say from personal experience;
1) Do not use Amsoil 75W-90 Severe Gear due to inability to engage gears without double clutching while cold and very notchy shifting when hot (and based on their lack of customer support, I will avoid them altogether going forward for all my cars and bikes, as will my bud), and
2) Do not bother with OTC Mobil1 75W-90 (much better than #1, but not OEM balanced feel with still some clunking between gears in lower revs that OEM fluid did not display).
I am now loading my 3rd and last aftermarket try with this before I surrender to OEM fluid fill (Mobilube PTX I believe). Based on GT3 owner bud recommendation and other research I will use Mobil Delvac 75W-90:
http://www.lufteknic.com/Merchant2/m...ode=lubricants
no association, just where I bought it from (although head tech took 15 minutes to talk me through lots of P-car questions and share his knowledge... clearly an enthusiast and teacher so it was easy decision to patronize them!):
I'll report back with my findings so anyone can learn from my 3 experiments.
note: Tech I talked to stated the LSD in my 40th is likely to have turned into an open diff after 10k miles with aggressive driving since clutch packs are known to be high wear items in the P-car LSD... take it for what it's worth.
I don't understand this statement. Is he saying the 40th transmission will lose its LSD? Is that why he recommends Delvac, since it works with both LSD and non LSD?
Whether 75-90 or 75-140 the oil acts the same when cold. The 140's pour out really easily when cold so I doubt they could possibly cause any damage. I know when I first go out in a cold AM session I don't have any shifting issues or resistance.....
Street GT3 996's have this issue though I'm not sure it translates over to the G96/01 transmissions found in all 996 C2's. The issue has to due with how loosely the GT3 diffs were set up from the factory. I've never heard of that being an issue with the 996 diffs which by the way are ramped at 25/55 IIRC. I'm currently racing one with Guard clutches/spacers but the stock ramping. It works great under decel, maybe a little loose on acel but I normally race a 50/80 diff....
I personally don't like Delvac for 996 C2/4 transmissions (G96/01). It's recommended (usually by dealerships) for GT3's (G96/96) and cup cars but your transmission is different internally and not as robust. I believe Viper 6's tech was referring to a GT3 fill. The Motul you looked at is a much better product for your needs.....
He was commenting on the fact that 996 LSD's like mine in stock form were high wear items... this being my first LSD I just listened. After friction materials wear it moves to acting like a semi or open diff... again, I'm n o LSD expert, just sharing what I heard.
Sounds like you have extensive P-car LSD experience and tuning... I think the tech was saying the clutch packs in the stock LSD were weak and I was niave if I thought after 10k that I still had a full LSD acting in there at that point... again, I have no experience so I just listened and appreciated his time and perspective.
He specifically stated Delvac was good for all 996 and they use for all their services including GT3 and is what they recommended and sell for that reason... good to hear your take on it as well however. I'll definitely post my experiences as this will be my 4th gear oil within 30 days... hopefully this is the one but I'm ok if not since relatively cheap experiment... trying 3 separate afttermarket is still less than buying OEM fill and will be one of my contributions to the rest of the forum so others may benefit... figured it would be worth a try so what the hell... as I learned from my fathers recent passing, you can't take it with you...
I used AC Delco Syncromesh in mine, It's not Porsche approved, but I have had luck with it in every manual vehicle I have owned. It was developed as a GM product with a special friction modifier for a GM truck transmission to save them from replacing all of the transmissions they sold and it worked. I have used it with awesome results in any honda transmission I have had including my civic with type r tranny and strait cut gears. All my Nissan trannies, my two M3 trannies etc. So when it came time to do the clutch, flywheel, RMS, IMS and tranny flush in my C4s, I figured I would give it a shot and have had awesome luck with that as well.
Well with Redline you need to specify NS if you do not have a LSD and thus do not want the extra friction modifiers. I've had good results in 987/996 with 75w-90 NS.
So 75w-90 would be your formulation:
http://www.redlineoil.com/product.aspx?product=57904
anyone try the Royal Purple brand??
i have a 1999 996, not sure what ill try when i change my manual tranny fluid.
I do know that when im driving on a hot day, my 2nd gear usually pops out when i try to shift from 1st to 2nd, but in the cold, when oil is thicker, it shifts beautifully.
maybe i should try a different viscosity rating.
I am very satisfied with it, it isnt approved for anything other than a few specific GM vehicles but is so over engineered that it is probably better than most MTF's out there. My C4S was a little notchy shifting between gears, most apparent between second and third. When I got the car I changed all the fluids, I put Lubromoly in the tranny which helped but not significantly. When I later did my clutch I figured I would give Synchromesh a try since whether I did it or not chances of my tranny needing a rebuild in the future were very likely. I have had it in for 15,000km and it is still shifting like a dream, fluid condition is still very good, and there were no shavings on my magnetic drain plug.
I've had the same experiences and generally agree with this although I would be hesitant to use on my p-car. The problem I have is that a lot of people use this as a bandaid to just mask and get their trannies to run longer when it should've really been replaced or repaired. I'd be curious at the long term effects on the Porsche tranny.
Here's why your tech is telling you your LSD is toast:
https://rennlist.com/forums/997-gt2-...sd-buster.html
The 2004 996 Anniversary vehicles got the same LSD as the 2004 GT3s, so they actually have decent ramps in them. All you need to do to make it a fully functional LSD is reclutch it...
Well I was freakin excited to find out I have a GT3 LSD. That lasted about 5 minutes until I read that thread. lol.
The big let down about that thread is when Bernie says there's a big difference in the gear oil you use, and then didn't say which ones were good.
John,
You should know by now that I don't make gear oil recommendations. There are 2 dozen good gear oils out there with very little performance or protection difference from one oil to the other.
I have two standard comments on gear oil. The best gear oil is the one that you change frequently, and I mean way way more frequently than Porsche's ridiculous service intervals.
Number two is there is only one oil that I tell people to never ever use, that is Redline Shockproof. The stuff was made for rear ends. That's the only thing it is good for. Don't put it into a transaxle where you've got gears and synchros in addition to a ring and pinion.
Viper, do you really feel this much difference bewteen these two? Mine only feels a little odd when cold. If your sure, I think I will order some too. I love to drain the fluids in my car and examine them. Im thinking about running a pipeline from the refinery to my shop.
Imre, my Dad loves this stuff for his tractors and equipment. What is your thoughts on it?
[QUOTE=KrazyK;10167218]Viper, do you really feel this much difference bewteen these two? Mine only feels a little odd when cold. If your sure, I think I will order some too. I love to drain the fluids in my car and examine them. Im thinking about running a pipeline from the refinery to my shop.
Ha, that pipeline will cut back on cost per fill. I am so pleased that I bought an extra gallon (ok I bought two at the same time hoping it was the one, but now I'm glad I did). I will say that I remember draining the OEM fluid and it had a unique pine tree smell and greenish tinge, both beyond standard GL5... the Delvac had this same smell and tinge going in when the others did not. I know its anecdotal, but I trust my nose and that corroborated what the Tech told me... this is the Mobilube PTX OEM fill rebranded/rebottled. I'm inclined to believe it now.
The most important thing is the stock performance is back as I remember... very decent shifting when cold and slick notch-free shifting when warm... I've now stopped kicking myself for dumping the OEM fill early... ha.
The difference between Delvac and the others is night and day, definitely go with the Delvac...Good luck!
All lubricants are sorted by Viscosity Index from highest to lowest.
Lubricants #: 2 & 3 in grey are Porsche approved.
All data except Viscosity at 0*C came from lubricant respective published data sheets.
All viscosities at 0*C were calculated using Mr. Widman�s chart and should be considered as approximate as most lubricants do not behave as Newtonian fluids.
Many thanks to Richard Widman.
http://www.widman.biz/English/Calculators/Graph.html
Mobilube PTX had viscosity at 0*C published by Mobil at 590 cSt and marked as Actual in the table above.
Below is the note from Mobilube PTX Data Sheet:
�The combination of synthetic base fluid technology and special high performance additives have been carefully formulated to meet the low temperature fluidity requirements of Porsche ( Kinematic Viscosity at 0�C of < 600 cSt)�
Enjoy,
=L=
Cool, empirical data is great! I wonder what the stats for the two other fluids I tried and significantly disliked are... Amsoil 75w-90 Severe Gear and OTC Mobil1 75w-90... Feel free to add these to your chart and re-publish all in one spreadsheet?
@40*C, cSt @100*C, cSt VSI @0*C, cSt
Mobil1 75W-90 99 15.2 142 937.6
Amsoil 75W-90 87.6 13.9 162 801
Amsoil 75W-90 SG 114.7 16.9 161 1135
Based on this my near freezing cold weather experience I should dislike the Delvac at least as much, if not more than the Amsoil SG... clearly there is more to it than just viscosity... seems easier to engage gears than even the Mobil 1 which has lower viscosity at comparable temps... hmm.
If I can find a P-car approved fluid for less than $40 a liter I'd try it...
This is a source reference. Confirm exact model applicability in the original material.
