Driveline rumble instant change with speed

[JHZR2]

Just bought a 93 Mercedes 300D 2.5 Turbo for my collection. It needs a few things but is a fun little scoot around car. Always wanted one, had been looking and this one just worked out.

Runs and drives really nice, needs minor window regulator and one door lock.

But on the highway, it’s perfectly smooth until I get to 60 mph. Then there’s a rumble someplace in the rear. Not like an unbalanced or bad tire. And doesn’t really vibrate the car. Certainly not the steering wheel.

Underneath all looks good from my inspection. Literally brand new so no I haven’t had it up on a lift and spent hours underneath. The basic checks all checked out…

But it’s weird that like 1 mph difference brings it on like a light switch. Most imbalance issues seem to gradually increase in intensity. Not this.

I’ve never had to diagnose a center support bearing. That’s my initial thought. I think it is kid dependent. At least somewhat.

Wheel bearings have never been so rumbly, though I guess I shouldn’t exclude that. Wouldn’t I feel a bad front bearing through the wheel? It’s been years since I’ve had a bad one.

Thanks!

 

[HankHill]

Nice car! I've always wanted one too. In my experience with bmw's, you maybe looking at your driveline or your rear diff. You're sure its not your exhaust right?

 

[HankHill]

Annnnd I just looked up a center support bearing, that's immediately what I was thing to by saying your driveline. My central support unit was going on my 750i and it just had a weird vibe at 70-73 mph that I could not solve. Had tires rebalanced twice, checked wheel bearings, bushings, you name it. Took it to BMW dealer very reluctantly, and got raped. My, whatever BMW called their center support bearing, was bad. THE ONLY WAY to get a new BMW part was to buy the entire driveshaft assembly and guibo joint. I could have purchased just the bearing unit aftermarket on pelican parts and set aside a weekend, but I had torn my ACL and MCL, there was no way I was getting under a car like that.
Check pelican parts, tons of quality parts for german cars, great catalog also:

https://www.pelicanparts.com/Mercedes-Benz/index-SC.htm

 

[HankHill]

Here ya go: https://www.pelicanparts.com/More_Info/0089814325.htm?pn=008-981-43-25-M34&SVSVSI=3311&DID=18566

 

[OVERKILL]

Annnnd I just looked up a center support bearing, that's immediately what I was thing to by saying your driveline. My central support unit was going on my 750i and it just had a weird vibe at 70-73 mph that I could not solve. Had tires rebalanced twice, checked wheel bearings, bushings, you name it. Took it to BMW dealer very reluctantly, and got raped. My, whatever BMW called their center support bearing, was bad. THE ONLY WAY to get a new BMW part was to buy the entire driveshaft assembly and guibo joint. I could have purchased just the bearing unit aftermarket on pelican parts and set aside a weekend, but I had torn my ACL and MCL, there was no way I was getting under a car like that.
Check pelican parts, tons of quality parts for german cars, great catalog also:

https://www.pelicanparts.com/Mercedes-Benz/index-SC.htm

I went through that on my M5 and got so PO'd I traded the car (I didn't buy the driveshaft, but it needed it). Regret that decision now, but a driveshaft without serviceable/replaceable u-joints just blew me away.

 

[HankHill]

I went through that on my M5 and got so PO'd I traded the car (I didn't buy the driveshaft, but it needed it). Regret that decision now, but a driveshaft without serviceable/replaceable u-joints just blew me away.

I guess people have tricks to getting parts and rebuilding them. There is a local big indy shop that three BMW techs started, and they took like 8 guys from their dealership with them. They are getting clients from CT coming out for services on their expensive models. Last time I drove by I saw at least 5 different M's there with plates from CT to PA in the lot. They've already gone through three different progressively larger facilities, and they're in an massive building now the size of a frigging warehouse. The are supposed to be able to re-build anything on the car, from high quality parts. They took so much talent from the two local dealership they've been advertising in every form of job wanted format they can find. I wish I could have gone there for my bearing, its probably have been half the price with higher quality parts.

 

[OVERKILL]

I guess people have tricks to getting parts and rebuilding them. There is a local big indy shop that three BMW techs started, and they took like 8 guys from their dealership with them. They are getting clients from CT coming out for services on their expensive models. Last time I drove by I saw at least 5 different M's there with plates from CT to PA in the lot. They've already gone through three different progressively larger facilities, and they're in an massive building now the size of a frigging warehouse. The are supposed to be able to re-build anything on the car, from high quality parts. They took so much talent from the two local dealership they've been advertising in every form of job wanted format they can find. I wish I could have gone there for my bearing, its probably have been half the price with higher quality parts.

Yes, they must, as Bavauto was selling remanufactured shafts, but the shipping to Canada was insane (as one would expect). I had already had the guibo replaced, and I had the new centre support bearing as well, but it became clear that it wasn't the issue, but rather one of the joints in the shaft.

 

[D60]

I went through that on my M5 and got so PO'd I traded the car (I didn't buy the driveshaft, but it needed it). Regret that decision now, but a driveshaft without serviceable/replaceable u-joints just blew me away.

Not that uncommon unfortunately. Subaru, Hyundai, Kia, Honda rear driveshafts, all staked u-joints. 1st Gen Taco double cardans are technically not serviceable, either (although it's possible). And some of the Ford F150 carrier bearings can't be serviced, you have to order an entirely new driveshaft

 

[OVERKILL]

Not that uncommon unfortunately. Subaru, Hyundai, Kia, Honda rear driveshafts, all staked u-joints. 1st Gen Taco double cardans are technically not serviceable, either (although it's possible). And some of the Ford F150 carrier bearings can't be serviced, you have to order an entirely new driveshaft

I was told it had CV-style joints in it, which is why it wasn't serviceable, but I didn't inspect it close enough to confirm, I was too PO'd, lol.

 

[HankHill]

Yes, they must, as Bavauto was selling remanufactured shafts, but the shipping to Canada was insane (as one would expect). I had already had the guibo replaced, and I had the new centre support bearing as well, but it became clear that it wasn't the issue, but rather one of the joints in the shaft.

If they were just throwing parts at it, they should have discounted you what you'd already paid towards the new driveshaft, albor included. Thats only fair.

 

[D60]

I guess people have tricks to getting parts and rebuilding them. There is a local big indy shop that three BMW techs started, and they took like 8 guys from their dealership with them. They are getting clients from CT coming out for services on their expensive models. Last time I drove by I saw at least 5 different M's there with plates from CT to PA in the lot. They've already gone through three different progressively larger facilities, and they're in an massive building now the size of a frigging warehouse. The are supposed to be able to re-build anything on the car, from high quality parts. They took so much talent from the two local dealership they've been advertising in every form of job wanted format they can find. I wish I could have gone there for my bearing, its probably have been half the price with higher quality parts.

I've heard of that with Subaru rear driveshafts, too. Some say if you tool up to do it you'll be as busy as you want to be. As a machinist I almost undertook this on a Baja for a friend, but in the end it was easier to just get a used shaft for him....but I was envisioning some jigs to nicely cut out the "stakes" so fresh joints could be easily pressed in.....

Big plans, big talk, little time .....

 

[OVERKILL]

If they were just throwing parts at it, they should have discounted you what you'd already paid towards the new driveshaft, albor included. Thats only fair.

Guibo had been replaced a fair bit earlier, I had ordered the support bearing because I knew that was getting loud, but closer inspection revealed that the noise I was hearing was the joint closer to the diff when it was up on the hoist. This was not at the BMW dealership, as I was allergic to them due to how much I was charged to have my clutch replaced.

 

[Nick1994]

Could be a rear axle bearing.

Take the rear wheels off, put the lug nuts back on so the rotors don't go flying, secure the car well and either set the cruise control or have someone bring it to that speed and crawl under and check.

 

[OVERKILL]

Just bought a 93 Mercedes 300D 2.5 Turbo for my collection. It needs a few things but is a fun little scoot around car. Always wanted one, had been looking and this one just worked out.

Runs and drives really nice, needs minor window regulator and one door lock.

But on the highway, it’s perfectly smooth until I get to 60 mph. Then there’s a rumble someplace in the rear. Not like an unbalanced or bad tire. And doesn’t really vibrate the car. Certainly not the steering wheel.

Underneath all looks good from my inspection. Literally brand new so no I haven’t had it up on a lift and spent hours underneath. The basic checks all checked out…

But it’s weird that like 1 mph difference brings it on like a light switch. Most imbalance issues seem to gradually increase in intensity. Not this.

I’ve never had to diagnose a center support bearing. That’s my initial thought. I think it is kid dependent. At least somewhat.

Wheel bearings have never been so rumbly, though I guess I shouldn’t exclude that. Wouldn’t I feel a bad front bearing through the wheel? It’s been years since I’ve had a bad one.

Thanks!

View attachment 94152

Definitely sounds more driveline related as others have noted. Check axle shafts and, as Nick noted, the bearings.

 

[Oillover]

I went through that on my M5 and got so PO'd I traded the car (I didn't buy the driveshaft, but it needed it). Regret that decision now, but a driveshaft without serviceable/replaceable u-joints just blew me away.

BMW's have had that design for generations.
My first experience was with my e30's. I too was PO'd when I discovered the "un-servicable" joints, especially after coming from a family with RWD Volvo's where u-joint replacements were never an issue. Also being in Canada, paying for a rebuilt unit from Pelican parts in the US was a big pill to swallow, especially when your a University student.

Sure, many claimed "just replace the center bearing/guibo and it'll be fine". But at that mileage, the joints themselves are wearing out and the imbalance is causing the whole driveshaft assembly to be out of alignment. Soon enough, you'll be back under that replacing the center joint/guibo again wondering "why'd it fail so soon?!"

To the OP, if your new ride has anywhere near 150k miles, save youself the time and hassle and simply replace the whole driveshaft, center bearing and guibo (if equipped) in one shot. You'll save yourself hours of diagnosing and questions wondering "where's that noise/vibration coming from?!" for years to come.
I did that on my e30 back in the mid 2000's and haven't had to touch anything in that vicinity since.

 

[Jetronic]

To the OP, if your new ride has anywhere near 150k miles, save youself the time and hassle and simply replace the whole driveshaft, center bearing and guibo (if equipped) in one shot. You'll save yourself hours of diagnosing and questions wondering "where's that noise/vibration coming from?!" for years to come.
I did that on my e30 back in the mid 2000's and haven't had to touch anything in that vicinity since.

I think you touched on the reason they sell complete units...

 

[bullwinkle]

I looked at one like that, believe it was a '92, not as nice as yours & it needed a $2K A/C evaporator job, but it ran like a scalded dog (compared to the '82 300D I had then). Isn't that front plate wrong? A 300TD is a wagon, it should read 300DT or D-T. I wonder if an HD driveshaft shop could test the driveshaft out of it to see what happens at higher speeds-maybe the guibo & a balancing could fix it?

 

[ka9mnx]

I chased the same problem with my 4Runner for a year. Toyota uses a, stupid, two piece driveshaft with a rubber isolation sleeve. I figured with the age and mileage it must be the problem so I shot gunned this one. Replaced the driveshaft with this one-piece and problem fixed. You may try looking up your vehicle at this place:

2000 Toyota 4Runner Drive Shaft - SKU 112060 - Free Shipping

2000 Toyota 4Runner Drive shaft, replaceable u-joints installed. Quality OEM fitment new driveshaft with warranty, fits 2000 Toyota 4Runner SKU 112060.

driveshaftstore.com

Toyota wanted over $600 for a driveshaft.

 

[JHZR2]

I went through that on my M5 and got so PO'd I traded the car (I didn't buy the driveshaft, but it needed it). Regret that decision now, but a driveshaft without serviceable/replaceable u-joints just blew me away.

Many of these don’t need it for a long time. At least on these MB cars, the driveshaft is essentially straight so there is no flex or movement unless some mount (engine, trans, diff) is collapsed. I had the driveshaft out of my 93 300SD which had about 291K miles at the time, and it moved smooth and perfect. I think for at least some of these cars, if they have t seen too much moisture or salt, the u-joints just don’t flex enough for it to matter, assuming the rest of the driveline is actually aligned.

 

[JHZR2]

I looked at one like that, believe it was a '92, not as nice as yours & it needed a $2K A/C evaporator job, but it ran like a scalded dog (compared to the '82 300D I had then). Isn't that front plate wrong? A 300TD is a wagon, it should read 300DT or D-T. I wonder if an HD driveshaft shop could test the driveshaft out of it to see what happens at higher speeds-maybe the guibo & a balancing could fix it?

Wasn’t my plate. I’d say you’re right… DT