I have a '97 XK8. At idle, with transmission in drive and brakes applied ( like at a stop light), car has a very noticeable vibration. If I shift to Neutral, the vibration goes away. No change in RPM when I shift back to drive. No difference in vibration if AC is on or off. Engine runs smooth, no codes, new plugs, MAF sensor cleaned, Valve cover port cleaned. Transmission shifts normally and no issues except the vibration at idle. Engine mounts look good, no leaks ( they have been replaced- 5 years ago).

I'm thinking it may be transmission mount, but mount looks good. Any way to check, or any special things to know about changing one. Also don't know if trans fluid has been replaced. Car has 125K miles, so willing to replace fluid if the vibration is an indication.

 

I would check the condition of the motor mounts. You might have one that is going bad.

 

Put it on the lift today, and find that the rear "dampener" on the trans bracket has been cut off. Found a replacement mount on Ebay, so went ahead and ordered it. May not be the issue, but can't hurt, since Jag felt it was important enough to put it there in the first place.

Also took pictures of the two engine mounts. Driver's side looks good, but there are possibly some signs of fluid leakage on the passenger side. I also had the normal Power Steering line leak on the passenger side, so this could be PS fluid residue. But based on the location ( sort of underneath the rubber top of the mount) I'm thinking it is the mount. Let me know if you concur.

 

Update. Bought a replacement transmission bracket with the Dampener. However, couldn't get the bracket out without dropping the exhaust, so decided to check the mount itself. Mount was bad, so replaced it on the bracket that does not have the dampener. Most of the vibration resolved, but still a little. Would like to swap the bracket, but reluctant to disconnect the exhaust if I don't have to.

Had a neighbor rev the car in gear, with the brake on, while I watched the engine. Left ( driver's) side of the engine bounced up about 4", so left side mount is bad. Found that strange, as the right mount was the one that showed some signs of leakage. Anyway, ordered 2 engine mounts, and will replace both. I'll let you know how she rides after the install.

Thanks for those that are following me through this restoration. FYI, to date I've invested $5200 just in parts . Just a benchmark for those looking to buy a cheap XK8 and "freshen" it up. ($1700 Susp, tires, brakes, wheels; $1200 interior; $1800 Exterior, including a paint job: $500 Engine, and I got lucky in that the Timing Chain upgrade had already been done.

 

Darbysan,

2 things to watch out for with worn motor mounts on our years.

1) the motion can wiggle the silencer out of the air filter box. It gets noticeably louder, almost wonder to yourself if there's a hole in the exhaust.

2) driving normally with cruise control on. Then when going up hill - cc turns off, display shows Restricted Performance. Everything resets with ignition cycle. This all comes from the vaccum hose into the throttle wiggling free from motor motion.back and forth. As soon as the car trys to adjust speed for the hill, it gets no throttle response since hose disconnected. Fyi, apparently they changed the cc method a year or two after ours.

Just wanted to give you a heads up. Risk goes away when new mounts installed.

 

FIXED: Got the new mounts installed today. Driver's side came out in two pieces. Passenger side was headed toward failure in the same manner, but not quite there yet. New mounts, with the new transmission mount, have solved the vibration at idle.

 

Thanks for letting us know it worked out.

 

Darbysan quote " FYI, to date I've invested $5200 just in parts."

Thanks for letting us know your progress. And updating us of your ongoing costs for keeping your XK8 on the road. I'm in the same ballpark on my 1999 XK8 convertible.

Slightly off topic, I tend to think a lot of people buy the X100 thinking it's a lot of car for their money, but then you have the task of renewing parts of the car that are 15+ years old. Hence the large bill both you and I have. That's okay as long as you expected that. People who walk into the XK8/XKR, without any knowledge, tend to argue that Jags are unreliable but this isn't fair considering the high cost of maintenance on any luxury old car regardless of brand. As I said.... slightly off topic

 

We have owned my wife's 2006 XK8 since early February 2012. Acquired at 36,000 miles, it now has 119,400 miles. I ran the updated numbers a couple of weeks ago and determined that I have spent $9,012 thus far for maintenance and repairs during our ownership period with approximately 80% of that amount being DIY. I have been driving since 1969 and this is indeed the most I have ever had to spend to keep a vehicle in top running condition....

 

Most of my costs were expected, as I bought a fairly cheap ( but rust free) coupe to start. I like to work on cars ( it's my hobby), so I wanted one that needed some love. A few of the items were unexpected, but not outrageous. I've been able to do all the labor myself ( except paint), so that keeps the costs down. If someone had to pay to have these repairs done, then it surely would have doubled the costs, and made it prohibitive to restore. At this point , baring a catastrophic failure of some part, I should be good to go for a while. Overall, I'm a little over the budget I had initially set, but think the car is worth it ( to me). Couldn't sell it for what I have in it, but I can drive it and enjoy. Plus, it gets better gas mileage than my other toys!

I was considering a Mercedes CL500 for my next project. A CL600 version was over $150K new, but can be bought for under $5k. but the costs of those parts is SCARY! $1000 per shock, $1000 coil pack ( both known problem parts),...Great car, though.

Jon, I went to college in Raleigh. Go Pack!

 

darbysan,

I am also an N.C. State graduate (but not a Dave Doeren fan). Weak early-season non-conference opponents (yet another one tomorrow) build false confidence and pump up the fan base year after year, then the team gets clocked by mediocre ACC opponents that they should beat. I expect the same-old same-old again this season....

I came close to purchasing a stunning 2015 M-B CLS550 in early 2018. But like you, the exorbitant costs of even DIY maintenance and repairs caused me to second-guess myself and step away from that deal. I am now over my former M-B fever....

 

Was going to tell you that the engine mounts and trans mounts are likely bad but you figured it out. That purple oil staining is the hydrofluid inside the mounts to dampen nvh

 

Interesting Raleigh connections. I was born there, but my family moved up to Maine when I was 5. My dad went to NC State, so I grew up rooting for them. His brothers went to Duke. I guess we just all can't stand Tar Heel Blue.

 

From my day, famous cheer was Go, Carolina, Go! Go to h----! Probably not many of us have Carolina Blue cars!

 

My late father was a Mercedes “man” with 3 M-B cars, so when I bought a BMW, he was so angry he didn’t speak to me for 3 weeks...

Apologies ... off topic