[porsche959]

how rough is your 6mt when it comes to bucking when you get on/off gas, in normal driving situations?

whenever i let off the gas, its almost like the car is getting a slight kick in the rear, no matter how much i let off (releasing the gas pedal 1mm still gets the same feeling).

my guess is that something is worn. could it be engine mounts/trans mounts? or a bad rear dif?

FYI I solved this by putting in new motor mounts and transmission mounts. No more bucking

[Welcome to NBA Jam]

It's pretty darn smooth for me in 1st, especially after a new clutch. You might need a new one.

[porsche959]

Originally Posted by Welcome to NBA Jam

It's pretty darn smooth for me in 1st, especially after a new clutch. You might need a new one.

so lets say your in 1st, driving 10mph, and you let off the gas, still in first. how does that feel? still smooth?

[Welcome to NBA Jam]

Originally Posted by porsche959

so lets say your in 1st, driving 10mph, and you let off the gas, still in first. how does that feel? still smooth?

It'll engine brake naturally but other than the initial pull backwards it's smooth.

[krhodes1]

Originally Posted by porsche959

so lets say your in 1st, driving 10mph, and you let off the gas, still in first. how does that feel? still smooth?

My car only has 46K on it, and it is still perfectly smooth when doing that - in fact it makes the driveline shunt (due to much softer motor mounts to quell th 4cyl shakes) in my GTI REALLY obvious.

I'd have a look at motor, trans, and diff mounts first. I would think anything worn in the driveshaft would cause vibrations. But maybe an issue with the dual-mass flywheel, could be a cause too if it isn't damping properly?

[Hannibal4444]

Tune perhaps? If stock I'd first check for any air leaks, dirty air filter or sensors, and reset adaptations. Basically the fuel prep system.

My 1st gear pretty smooth, but my 2nd gear grinds unless I engage it super slow. Killed a lot of the street driving experience and was saddened to read that this was normal.

[hassmaschine]

Mine is smooth. No grinding either -150k, original clutch.

I don't think grinding gears is "normal"...

[tcphoto]

I have had no issues with mine so I'd start with lifting it up and inspecting all the rubber parts.

[oVeRdOsE.]

hahah, Ive described the exact same thing in an other thread. '' someone kick the car''

same issue here.

Ive just got the car, and waiting to do oil change before looking further in that issue.

[porsche959]

Originally Posted by oVeRdOsE.

hahah, Ive described the exact same thing in an other thread. '' someone kick the car''

same issue here.

Ive just got the car, and waiting to do oil change before looking further in that issue.

Ha that’s actually why I started this thread, you described it exactly as I felt it, but I could never put it into words.

I’m not getting any grinding, just bucking. As in the car lurches forward.

[oVeRdOsE.]

Originally Posted by porsche959

Ha that’s actually why I started this thread, you described it exactly as I felt it, but I could never put it into words.

I’m not getting any grinding, just bucking. As in the car lurches forward.

-it was hard to described, I had a set of tires in the car, at first I thought it was the tires moving.
-Then I was pretty sure that was transmission related.
-Then I thought about a missfire, but I don't have any code...

Anyway, during my maintenance stuff, Ive noticed 2 things.
- both center sparkplug were full of oil. Common problem on those n52. Ive cleaned the coils and plugs.
- passenger side ground was broken. I fixed it with a 8gau wire.

Didn't ride the car yet.

[6Inarowmakesitgo!]

Originally Posted by porsche959

how rough is your 6mt when it comes to bucking when you get on/off gas, in normal driving situations?

whenever i let off the gas, its almost like the car is getting a slight kick in the rear, no matter how much i let off (releasing the gas pedal 1mm still gets the same feeling).

my guess is that something is worn. could it be engine mounts/trans mounts? or a bad rear dif?

As stated, check all the mounts and make sure they are not sagging/squished, but also look at your driveshaft rather closely. I have felt a ujoint that was on its way out do exactly as you are describing, and if the ujoint is failing it’s probably indicative of tired mounts. BMW ujoints typically get stiff and notchy as they age though. Check guibo too, they can tear.

[Donutz]

If I let the gas off smoothly I don't get any kick in first. If I come off abruptly the transition is rough. In my case my dmfw is shot.

[porsche959]

Originally Posted by oVeRdOsE.

hahah, Ive described the exact same thing in an other thread. '' someone kick the car''

same issue here.

Ive just got the car, and waiting to do oil change before looking further in that issue.

FYI I solved this by putting in new motor mounts and transmission mounts. No more bucking

[oVeRdOsE.]

I also figured out my ''kick in the transmission''

front drive shaft ubolts were shot.

huge loose.

I need to find a drive shaft now, rockauto and FCP euro don't carry them anymore...

[Efthreeoh]

Originally Posted by oVeRdOsE.

I also figured out my ''kick in the transmission''

front drive shaft ubolts were shot.

huge loose.

I need to find a drive shaft now, rockauto and FCP euro don't carry them anymore...

Just to make sure, you mean "u-joints" rather than "ubolts"...

Contact Driveshaft Specialists of Texas, they'll probably have a fresh rebuilt shaft in stock or will rebuild yours. They are an excellent source for BMW driveshafts.

http://www.driveshaftspecialist.com/...0html/BMW.html

[Efthreeoh]

Originally Posted by porsche959

FYI I solved this by putting in new motor mounts and transmission mounts. No more bucking

Any chance you can post pics of the blown mounts? It'd be interesting to see what they look like.

TIA

[oVeRdOsE.]

Originally Posted by Efthreeoh

Just to make sure, you mean "u-joints" rather than "ubolts"...

Contact Driveshaft Specialists of Texas, they'll probably have a fresh rebuilt shaft in stock or will rebuild yours. They are an excellent source for BMW driveshafts.

http://www.driveshaftspecialist.com/...0html/BMW.html

ujoints indeed.

thanks for the link !

[dcorn]

Engine\trans mounts solved my problems as well. I'll have to check the driveshaft, but I would think that would cause a ton of vibrations at highway speed.

[oVeRdOsE.]

Originally Posted by dcorn

Engine\trans mounts solved my problems as well. I'll have to check the driveshaft, but I would think that would cause a ton of vibrations at highway speed.

no vibration, if the u joints are shot, the shaft will spin freely for like a 1/5 of a turn. In the FCP video you can tell the the shaft pin hole metal part is what that block the rotation.

While doing my transfer case oil change, Ive noticed that the shaft was loose.

So it gives a ''kick'' when the rotation slows down then get back up.
On the highway, it gives a smoother kick, but still there.

no metal sound, since the metal parts are not touching yet, but its coming soon.

Solutions :
1- get a new one @ xxxx $
2- rebuilt it, according to internet this is a hard job getting those universal joint out. so you'll ending up with 4 hours job + parts, around 400-500$.
3- get a salvaged one. They should last 200 000km if they are greased up on a regular maintenance.
4- remove it.
5- leave it, it won't break so easily.

I choose option 3, since its my beater, and here we got a tons of smashed E90 xdrive.

On upull scrap yard the part is 30$ , and of course all yard I've called the transmission is the 1st thing that goes. On FB I got 3 prices, all 200$.


The tranmission mount was fine, no crack. But I fill it with 3M windshield sealant anyway, aka bushing maker.

[ccraig13]

Interesting, I'm experiencing this same issue. Thank you for documenting it!

[oVeRdOsE.]

Just realize on my E91 I have a jobber front drive shaft while removing it !
it also got a grease port.

I'll ditch the used OEM drive shaft, and rebuilt mine for sure.

BUT !

What is the universal joint part # ?

Ive looked on amazon, ebay, realoem and now I've send a email to Dorman.