I've started to notice a bunch of slack/slop in my R53 drivetrain over the last few months. It seems like off throttle/on throttle transitions are really rough...like there is a lot of slop in the transmission, or drivetrain somewhere. If I'm coasting down the road off of the throttle, and then I get on the gas hard...it shakes the car pretty good. It just feels like something is sloppy and not tight.

At first I thought it might have been a bad engine mount, allowing the engine to twist back and forth when I was on and off of the throttle...but I checked the mounts, and they are fine. What about the from CV joints/axles...could they be getting sloppy? I doubt it's the transmission....what else could it be?? Any other bushings that could be going bad and letting things move around? Any ideas?

 

if you are on original R53 mounts and bushings, they are likely all shot. for me, the lower motor mount was the "miracle cure" for the slop. now I can let off the throttle without it being a 3 second careful process to avoid the "jerk". Top mount on passenger side is the one everybody sees and fixes, and rightfully so, but switching to the vibratechnics bottom mount made the world of difference for me.

 

The engine/tranny mounts....
Suggestion....
Way motor works still sells the old TSW dogbone style stiffener you add to the OEM top mount, packaged with new tranny mounts.... The mount gets you much less nvh than the solid mount... And seems to extend the life of the failure prone top mount. VIP was selling a similar mount...not sure if it is still around.

 

Engine or tranny mounts. Get them looked at or do it yourself if yer handy with that kinda stuff.

I had both engine mounts replaced on the passenger side this summer. The hydraulic one was empty (What a pissah!) and the bottom one's rubber bushing was worn.

 

Thanks for all the info guys! For those of you who are running the stiffer aftermarket tranny and engine mounts, how much more engine vibration are you feeling through the steering wheel and pedals?? Is it noticeable? or no big deal?

Thanks

 

I have Vibratechnics upper and lower mounts, and powerflex poly inserts in my tranny mount. All three help quite a bit, but there is still a bit of on/off throttle slop that you describe. Really drives me crazy to be honest....but im hypersensitive when it comes to my cars

Assuming you are on the stock clutch/flywheel, it is my understanding that the stock dual mass flywheel is the culprit. I will tell you, after I've had my clutch and flywheel replaced the slop was gone, but slowly returns. If you've ever seen the stock flywheel out of the car, you will see that it is sprung and will spring back and forth (rotationally). This gets worse as they wear. Also, this slop is more pronounced the more power/torque you are putting through it.

 

I had the exact same issues as the OP describes regarding the sloppy feeling engine.

I ended up having to replace my header /cat and then found out from other club members that bad engine mounts can lead to this failure ($1200 job with a used header).

I replaced the lower and passenger mounts (even though there was no sign of leaking) with Vibratechnic mounts.

The NVH is noticeably up. Idle at round 800rpm is really annoying and the overall experience is more visceral. I've picked up a new "growl" or "chatter" in the cabin at WOT off the line (not vibrations or squeaks, but engine sounds). When driving, the noise is not that noticeable, but the vibration can be compared to about 1/4 of what driving on grooved pavement (that is about to be re-paved) feels like. Defintely up from the smooth it use to feel like, but not horrible. I'll get use to it soon, and the rubber will break-in.

At the end of the day, the shifting is now fabulous, and the NVH is livable - because: racecar

 

I'd suggest you polybush the engine mounts and gearbox, if they haven't already failed, or if they have then upgrade to Vibratechnics, and then just live with a little NVH at idle ... and enjoy the improved feel.

 

The VT mounts will loosen a little bit in the first 1k miles after install and reduce the nvh from their super stiff "brand new" condition.

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