SOLD: E30 E36 E39 E46 Z3 and Z4 Manual Gearbox Mounts - Ruff Brand from SpeedFactor

[wrs 120]

I purchased these only a week or so ago from SpeedFactor and installed them yesterday. They we marketed as similar to the OE mounts with only a slight increase in noise level (even rang SpeedFactor to check if they would be suitable). Bzzzttt, wrong - they couple every bit of vibration, shake, wobble and transmission noise into the cabin. It's worse than having no carpet. They might work better if the engine mounts were changed at the same time. I've changed back to OE gearbox mounts today and the car is nice and quiet again.

Likely would best suit a racecar. I don't want to toss them so they're free to whoever wants them - just pay the freight cost of $11.00 for NZ Couriers E20 bag + $1.50 for a residential ticket if not a business address. Only thing missing from them is the flat washers as I pinched them to use on the OE ones.

See Trademe Auction for details: https://www.trademe.co.nz/motors/car-parts-accessories/bmw/other/listing-2678003020.htm?rsqid=bc379d6323674d49a4c26e9987045d75-002

Edited July 2, 2020 by wrs

[slideways 47]

PM'd

[wrs 120]

Yours - now sold (for free)...

[leichtbau 525]

Poor form from Speed Factor!

[wrs 120]

2 hours ago, 3pedals said:

Ouch - that's a big hit @wrs - I'm going O.E  on engine and gearbox mounts plus a new flexible coupling, figured its done well to hang in for 285,000 km 

 And  slideways should send him at least a box of beers  in return 

Not the biggest hit I've had on the road to learning. I took the guys at SpeedFactor at their word when the said they wouldn't be much louder than the OE ones - maybe they didn't really know. When I rang them to comment about the noise level increase they did say the noise coupling might have been worse because the engine mounts weren't changed to stiffer types at the same time meaning all the vibration was transferred into the trans tunnel instead of distributed across the whole front of the chassis. Even so, I suspect they still would have been much too noisy for most people unless they were building a track car.

[zero 1162]

Its very common to get noise and vibration from the trans mounts if they are overtightened.

The torque spec for the nuts is very low.

[wrs 120]

The fixing on each side is a stud similar to the OE mount. I doubt overtightening would be the problem. They have a special semi locknut so don't need to be very tight.

[zero 1162]

Did you use a torque wrench?

This is a very common problem for aftermarket trans bushings on our cars and widely documented online.

Some manufacturers have even had to put special disclaimers on their websites regarding tightening because they got so many complaints from people who over tightened and then experienced problems.

[wrs 120]

@3pedals, totally agree - I'm now sure the engine mounts needed to be changed at the same time. However, even if they were I'm sure the overall noise still would have been too much. I further suspect that when changing to aftermarket engine and/or gearbox mounts it's important to match the two to make sure they have the correct characteristics so they don't fight each other.

@zero, I don't think the torque would have had anything to do with the problem in this case even if it was wrong. The mounts have a plate and stud bonded to each side with a solid rubber/urethane combo in between - essentially a copy of the OE mount with more and stiffer rubber with a small cup on one side. It's not like a bush with a bolt through it that's been squished too much due to too much torque. In the case of the mounts in question, you could likely torque them up until they almost stripped and it would make zero difference to the level of vibration. They were not over-torqued anyway and it was easy to undo the nuts when I removed them.

With the new OE mounts I did torque them up quite tight - much tighter than the Ruff ones and have no problem with any vibration or noise issues.

Edited July 3, 2020 by wrs