So what happened to my bullet proof transmission!

Everything was fine, then I pulled out onto the boulevard, I felt a small lurch, then a terrible grinding noise. The noise seemed to be forward, even like it might have been something grinding on a front tire. I limped it about 500 feet to the nearest safe place to pull over then parked the car. I did a walk around and didn't see anything. So I popped the hood, started it up and the noise was still there. It appeared to be isolated to the back side of the engine bay. It almost sounds like something grinding on the flywheel. The noise did come and go a bit based upon the gear, but it never completely went away. The lurch I felt, almost felt like something getting caught in the flywheel, but I'm really reaching here.

Any ideas would be appreciated!

 

The early MB transmissions have a weak bearing -- it was updated around 2000 -- I believe with the W210 refresh that used the transmission.

I forget exactly what they did -- sleeve bearing to roller maybe. My memory is that it is located at the front of the box. The part can just go and it can be fixed if it has not taken out the inside of the box.

Obviously you have had an unusual occurrence -- sorry

 

Thanks Yeltdog for the tip. It could very well be the bearing. One mechanic I spoke with today had suggested that it might be. Additionally, it makes sense of it being a mechanical failure as there are no codes and the transmission does shift, at least into second and reverse. I didn't go fast enough to see any other gears, but my guess is that they are fine. Another mechanic has mentioned that it might be lower planetary gears, but I don't think that would account for the noise at idle in park as it would be my understanding that they wouldn't be turning at that point.

 

The MB box is used in a wide variety of vehicles -- My porsche turbo has basically the same box. It was the only transmission at the time that was able to handle high output engines - so a lot of cars used it.

Unfortunately, I can't remember the particular points of the fix. The shaft was changed with the upgrade so I know that not all the parts are backward compatible.

I had a friend that was a transmission builder that I could always go to -- a bad heart took him all too early. Finding someone who knows what they are doing is very difficult.

 

Yes the problem does sound unusual. I have a W210 (1998 E320) and have not heard of this problem. Here is a link to the Mercedes web site I am a member of and all you want to know about the transmission. The transmission and engine are pretty much none issues with this car. Its other problems like the A/C, window regulators, and RUST.

Mercedes-Benz 722.6 Transmission FAQ - Benzworld.org - Mercedes-Benz Discussion Forum

 

Well the XJR is being towed to the transmission shop that I selected after many conversations with owners... Hopefully this afternoon they will have a reasonable diagnosis of the issue. I am confused by the sound being generated in any gear as well as park/neutral.

I'll report back after they call me.

 

Hope it's a simple fix, keep us posted.

 

Well it was about as fatal as it gets.

A thrust bearing disintegrated in the rear carrier taking most of the gears with it. I viewed the damage this evening along with the new parts. The design of the original carrier had nothing to keep the bearing and race in place except pressure. The new carrier design has two notches that the new race fits into. This keeps the race in place so only the bearing can rotate. I will end up with essentially a new transmission out of this as they are rebuilding the whole tranny. The torque converter will be back from it's rebuild tomorrow, and the bearing is the last part to arrive as the first one that came in was for the wrong model. Hopefully it will back on the road no later than Friday. From all the additional research I did, it appears that Mercedes updated this transmission for model year 2000 at least in their product lines. I can't confirm that the Jaguar variant would include the upgrade but I would assume so.

This is just one example that even the best transmissions can have catastrophic failures. They assured me that there was probably nothing I could have done to prevent this failure including more frequent fluid changes. I'm not even sure I had detected a noise ahead of the failure. One time I thought I had heard something but I was never able to detect it again so I didn't do anything. So my $9000 XJR (1yr ago) just turned into $14000 with this new investment!

It is kinda ironic that recently I have responded to numerous posts where noobies have been asking XJ8 or XJR... and of course I responded... get the XJR it has the better transmission!

 

Sorry to hear it was indeed the bearing failure -- nothing you could have done to prevent it. From my understanding it was indeed upgraded for model year 2000 -- so they must have been available in 1999 at some point. That is why it is often recommend to get a 2000 or newer XJR


From an unscientific look at the failure: I see it more often discussed with the higher powered MB cars -- The v6's don't have a lot of discussion regarding the failure. So it must just be the added stress of the higher power. My MB wagon has the same updated transmission -- although that is a V6 car.

In my Porsche group we have never had a failure -- but the car did not come out until 2001 -- so they all would have the update.

 

I sense a bitter taste, 5000 to rebuild the box? that is VERY expensive. Must be a top draw rebuild, I guess parts swallow a major part of the bill.

 

It is very expensive, they are doing everything. The major hard parts and the torque converter are where the majority of the cost is, and of course, the rest is labor. I did pick one of the more expensive yet reputable establishments and I wasn't willing to compromise on the tranny. Of course, they call me today and the second bearing that was sent was still the wrong one, it was the original version, so they got on the phone and made sure that the right one was on the way. The had the quy at the parts house get out him mic and mic it and visually describe it. They should have had him email a digital photo, but they didn't think of that. So hopefully they get it back together and in the car before 5pm!

 

Well, I finally got it back last night. It shifts better than when I bought it 30K miles ago, of course with nearly all new parts, it should. They replaced both sets of planet gears and rebuilt the torque converter along with the bearings and a basic rebuild kit. There were $2777 in parts and fluid alone, so this is a close to a new transmission that I can get without actually buying one.

As I never drove the vehicle new, I can only imagine that this is how it performed then. It is tight, responsive, yet smooth as silk.

Now for the bad, some a**hole stole my leaper sometime in the last two weeks! The first shop I had it towed to, had to keep it outside for the first night, that must have been where it happened. That just pissed me off, why can't people keep their hands off other peoples property! If anyone has a spare leaper they want to part with let me know.

 

Good to hear she's back and performing well, bad to hear of the leaper thief - I know of a very rare bronze one you could have, but I bet it'd be expensive...parts yards in the USA should have them, more rare over this side of the pond because of bl**dy health and safety laws.

 

Are they afraid that when you run over the jaywalking pedestrian, or however you refer to them there, that they might get impaled on the leaper?!

I have found a brand new one for $120 at Captain Jaguar's Cathouse. Only about $50 more than used, so I will probably go that direction.

 

I used to find my leaper turned around facing the windscreen every day coming out of school, annoying but at least no one broke it off. I have purchased floor mats and some other things from this welsh enterprises, they seem like a reasonable place

Welsh Enterprises, Inc - Jaguar XJ8 (98-03) Body Fittings Bonnet (Hood) Area Parts - Leaping Cat With Spring Loaded Base

good luck