Suspension Maintenance

After a search with no meaninful result, here is the question: Since our 996s are 10-15 years old, what are some suspension maintenance items to consider? 1. Shocks/Struts? 2. Control Arms? Links, etc. 3. Bushings? 4. Etc. At times I hear a very subtle rattle come from the front suspension and I wonder what is a suspect. Thanks.

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Pretty much up to you what you want to do. Well, you and the car. Some owners will I'm sure decide at some point to have the suspension renewed. This might be due to symptoms calling for this or the decision may be made on just time/miles. Since my Boxster is going on 12 years old and has covered over 286K miles shocks/suspension and what have you is a bit of a concern to me. The car feels ok to me but once in a while -- not every service but once in a while -- I ask a senior tech to road test my car and advise me if he believes the shocks/suspension, or steering, shifter, clutch, anything really, needs attention. So far the tech has come back with "performs as designed". The techs tell me shocks are generally ok unless they show leaks. 'course, if the car porpoises when it encounters a dip/rise in the road even if the shocks are leak free, the shocks are probably due to be replaced. In my car's case tire wear is even, and tire life is very good, and during the occasional alignment the tech has not found anything amiss. The car aligns quite well with no big adjustments needed, or inconsistent adjustments needed to bring the alignment into spec. During every service -- which occurs at least every 5K miles (oil/filter service) -- the tech also performs a thorough inspection of the car's undercarriage. Often I'm under the car with the tech and he walks me around the car. One time we spotted some cracked boots on the front sway bar drop link joints . The tech said over time the exposed joints would gather dust/dirt and wear, so I had these replaced. Another time the tech spotted the CV boots were failing and based on his advice I had him remove the shafts, clean/inspect the bearings (they were ok), then repack with grease and fit new boots and install the shafts. That was maybe 40K miles ago and so far the CV boots/bearings are performing just fine. Initially I wanted to just replace the shafts but their replacement cost ($900+/each) and the tech telling me these often last and last and last had me give him the go-ahead to clean/inspect and repack. This proved to be a bit less expensive than the replacement route which was a plus. So, it is pretty much up to what you want to do. You can be proactive and replace/renew: New suspension hardware (factory or aftermarket), shocks, springs (?), and related hardware (like perhaps new engine/tranny mounts). This is expensive but it is your money. If you choose to go this route, how you will resist the urge to replace/renew all the cooling system hoses? Or you can just continue to monitor the handling/behavior of the car -- with your trusted tech's assistance -- and when something comes up fix/replace in a manner deemed appropriate by the tech. For instance, say a shock develops a leak. The tech almost certainly would advise you to replace both shocks, but he might advise you to replace all 4. At this point he might advise other work. Or the decision might be out of his hands based on what he finds.

^+1

Here is what I do. Check the suspension once a year, if you find a worn part, replace it. It's not rocket science.

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Once a year is a bit infrequent. While not directly related to suspension one concern I would have is with the CV boots. These can split/crack/fail at any time and to run with a cracked CV boot any time at all -- let alone worst case a year -- would almost certainly have the CV bearings contaminated and thus rendered unable to be resurrected by cleaning and repacking. Admittedly my cars get inspected probably a bit more frequently than most but I drive a lot of miles, I'm cutting back though believe it or not, and my cars require more frequent servicing because of how much I drive them. When the car is in the shop I have a standing order the tech inspect the car for any signs of problems anywhere from something in a tire to a fluid leak or worn brakes or even a damaged underbody plastic panel.

Chances of a CV boot splitting are pretty slim and most don't split right at the joint but usually a few inches away from it so most of the grease stays in the joint for a long time. Also, you will see the condition of the boots when changing the oil anyways. No need to over think or over complicate this.

All, thanks! What about control arms? So far what I hear is not severe enough for me to suspect control arms and bump stops. Perhaps he rubber is getting a bit dry though.... As far as engine/tranny mounts, honestly I haven't checked. I'll look into it. Any particular sign when engine mount is gone? From my past experience, I have heard funny noises and clicks from the engine bay, but those were front engine. This time the noise is subtle but from the front, which is not where the engine is.

At the last "up on the lift" inspection for my '99 911 w/76K miles, the tech said the front stabilizer link bushings were showing wear (part #: 996-343-069&070-04). But I have not yet detected any noises or problems emanating from the suspension. These parts are $125 each at the dealer...Pelican has them for $30-35 ea. My intentions are to follow up/monitor this issue at future inspections. Your comments will be appreciated. relinuca

When the those bushings start to clunk, change them.

I plan to have my oil and filter changed every 5k. At each time I plan to have the suspension and undercarriage inspected, as well as motor and transmission mounts. At 11 years age and 40k miles not of these areas show a problem. Since I am the newest owner I carry the burden of previous owners sins when it comes to service.

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Given the work I've done on the various cars (replaced 996's suspension with x74, brake jobs, (minimal) track prep, do my own wheel alignment, replaced the minivan's struts, replace alternator and starter cable, etc.) people at work are amazed why I don't do my own oil changes. The main reason is that I want somebody who sees these cars every day to inspect everything on it and test drive it at least 2x/year and the oil/filter change is a great time to do so. That should catch any suspension issues and other things that have been mentioned without extra checking. Although, along with bad IMSB and RMS replacements done by the incompetent shop who did my PPI, they left loose a diagonal brace after replacing the tranny that slowly worked the bolt out and started squeaking like crazy. It took me a month to find what that was.

Did this shop make any other mistakes besides forgetting to tighten a crossbrace?

Quotes source post: 11790561

I think that's a reasonable approach. Even when I did my own oil/filter services I still checked the car out from underneath while I had the rear end up on ramps. Now that I have my cars serviced I always welcome a 2nd pair of eyeballs on my car looking for issues. Between services barring any abnormal behavior or symptoms all I do is every time I walk up to the car I look under it -- from afar so I do not have to get down on my hands and knees -- for any signs of a fluid leak. I keep an eye on the oil level - from inside the car -- and monitor the gages -- coolant temperature in the Boxster and coolant temperature, oil pressure and voltage in my Turbo. I am alert to any odors from the car. Often a coolant leak is first suspected by smelling anti-freeze from the hot engine/car. This is what first clued me in that my Turbo had a coolant leak at its water pump. However, I sometimes get a false alarm once in a while when say walking up to my hot car in a parking lot and catching a whiff of anti-freeze. I have to remind myself to check the vehicle next to mine and determine the odor is coming from the other car. Sometimes a glance under the car next to mine has me seeing a puddle under the car. I hate to admit it but I very seldom check the coolant level and I seldom if ever check the power steering fluid level or even the brake fluid/clutch fluid level. Oh, if I have the engine compartment lid open on the Turbo I look at the reservoirs for signs of any fluid leak and if possible a low fluid condition -- as long as I do not to remove a cap -- but that is all. (I haven't seen the Boxster's engine exposed in years.) When starting the engine and when driving the car I monitor the sound of the engine (and the drivetrain, et al) for any noises that might be an early warning of something amiss. Caught my Boxster's water pump going bad by investigating the source of a low rumbling from the engine that developed as the cold engine ran and warmed up. To me all of this is part of what is necessary and right to catch anything that is going wrong before it escalates into something serious, perhaps leading up to a dead engine.

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1) Even though it was my PPI, when they found metal in the oil filter they talked with the current owner first instead of me. I don't know what they discussed but the net result was that they said no problem, we'll replace the IMSB and you'll be good to go. 12k miles later the new (LNE) IMSB was toast. I was naive about this at the time, but they clearly did not follow any of the guidelines or requirements for IMSB replacement when the current one was already damaged. 2) Also replaced RMS which was leaking. At engine rebuild 12k miles later, the new RMS was falling out of the case. My understanding is that LNE is no longer providing IMSBs to this shop.

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Ahh ok, I remember your thread now.

Macster, Like you, me and many other DIY gearheads suffer from the same thing. Always listenning, feeling and smelling the car when around it. I have experienced the same things as you and get a momemt of panic when smelling coolant in the air or hearing something banging or making noise while in traffic, only to realize it's someone else's car that's doing it. BUT this is the only way an owner will catch problems before they become a big problem.