Subframe bushings. Once and for all. Which is best for a street/track car?

[bennyfizzle]

So the final piece to my project's puzzle is the subframe bushings. I really don't want to go OEM simply because of the hassle of reinstallation. I've heard people having issues with the Powerflex bushings and their washers. I also know there's a few different versions of the Powerflex bushings.

I don't want to do solid because this IS still going to be a street car somewhat regularly.

Car is a 93 318 with 95 m3 running gear (subframes, trailing arms, blah blah blah, everything.), currently have THR eyeball arms up front, TMS solid diff bushings out back, OEM RTAB with TMS limiters, stock control arms and all new balljoints.

I don't like the idea of stacking washers and what not just to get a bushing to fit right. I want something that is stiffer than oem, won't wear out and crack quickly, and the ease of installation of a poly bushing.

Make your recommendations and share your experiences!

[hinzm3]

I installed powerflex subframe bushings. I don't recall any issues with the washers and haven't had any issues since. Installation was a breeze and its the route I would recommend. You would have to be crazy to install solid bushigns if the car is still driven on the street.

[BMWParkingOnly]

Solid......if you think you're man enough.

[NeilM]

Unless you've also had the M3 trunk floor reinforcements welded in, you want to be conservative about using harder subframe bushings. I'd either use stock M3 parts, or else nothing harder than PowerFlex purple/sport poly bushings.

Neil

[bennyfizzle]

Plates are in fact going in, so no worries on the poly. Just wanted to make sure I order the right ones.

[EastBayBimmer]

Anyone have experience with the UUC ones?

[VengeanceM3]

Anyone have experience with the UUC ones?

Or the AKG poly?

[VictoryGarland]

I have a friend with solid bushings on his 240SX/S14 rear subframe. Its really not that big of a deal on a street driven car. Your results may vary with solid diff mounts though.

[Mad Dog 20/20]

I don't like the idea of stacking washers and what not just to get a bushing to fit right.

The P lex washer issue is not a "fit" issue, so much as a weak part issue. The supplied washers are too thin/weak and cup over time. Stacking the supplied washers with the OE ones resolves/prevents the problem.

P flex purps

[dswads34]

Granted I have yet to track the car, but I am very happy with the UUC poly subframe mounts. I can't compare to anything other than stock though. They help to put the power down very nicely, and they aren't harsh at all IMO. For reference, the car also has delrin diff bushings, poly motor/trans/RTABs, and a completely refreshed/rebuilt suspension. HTH!

[gotboost?]

I have reinforcement plates and aluminum bushings on my street car. They were pretty damn loud for the first few days, then I got used to them.

[Feuerräder]

Or the AKG poly?

I've got the AKGs and reinforcement plates. NVH is just about the same as stock, installation was pathetically simple, and the back seems a bit more solid. One thing I've noticed, though, is that I have the thuds symptomatic of subframe failure ever since I did the install, but that may be the AKG poly diff bushings that I installed at the same time, and everything is structurally sound.

[catalyst.]

the powerflex race ones are what i have.. i like them but the washers are absolute trash, you cant even think about using them the way they are.

[M3 Muscle]

I replaced EVERYTHING in my rear suspension. The last thing I tackled was the subframe mounts. I got two out and painstakingly got two OEM mounts back in. After that I called it quits!!! The old mounts were not worn out. They had ~107K miles on them and the car is a '98. Are yours really worn out? I think these are the only suspension bits BMW designed NOT to wear out.

If they are actually worn out, I would run the purple Powerflex. I would just re-enforce the weak washers with the OEM washers or regular bolt washers. I would weld the two together though.

[bennyfizzle]

I'm just so sick of the E36 drivetrain lash/clunk. The last things I had to replace before I wrecked the M3 was subframe mounts, all the balljoints out back, and the driveshaft. I'm doing all of that now, and I want a solid rear-end. I don't want any god damn clunks from throttle inputs. So Powerfles purples with reinforced washers it is.

If they start clunking I am personally going to hunt down you all.

[Chris@RRT]

Are you sure your clunking is coming from the rear end? I run stock 325 subframe bushings and stock diff bushings, and have no problems whatsoever. I found most of the drivetrain lash / windup in the e36 was a result of the dual-mass flywheel and soft engine and transmission mounts.

The two pieces of the dual-mass move relative to each other, which contributes to the driveline lash. It is, however, wise to be careful about using a single mass unit as the dual mass does serve a purpose in that it reduces internal engine vibration (and problems like loosening bolts and nuts, broken parts, etc).

[catalyst.]

i dont see why you would go with the purple personally, i dont even notice any vibration with the black race bushings and im willing to bet they will last much longer. A lot of people say that the thing that makes the most noise in the rear is poly diff bushings.

[IWannaBMW]

Get you some uuc red racing tranny mounts, it'll make a big difference as far as drivetrain movement.

[bennyfizzle]

I already have a JBR Ltw Fly, UUC Black mounts with enforcer cups, fresh motor mounts, blah blah blah.

If you put your hand on the rear floorboard in 2nd gear and tapped the throttle it sounded like someone was whacking the car with a mallet.

diff bolt is/was fine.

[M3 Muscle]

I'm just so sick of the E36 drivetrain lash/clunk.

I can ALMOST promise you that the differential bushings are not causing a 'clunk'. When I actually had a clunk you could feel in the floorboard, I had a broken tranny mount. It felt the EXACT same way...felt like someone hit the floorboard with a rubber mallet. That took 6+ months to find since I kept snooping around in the rear end.

My RTAB's were shot, and I still didn't have a 'clunk'. The only thing suspension wise that might have been considered as a clunk, was worn out control arm ball joints. I didn't notice them when I replaced my RTAB's so I was able to isolate the problem.

[bennyfizzle]

I can ALMOST promise you that the differential bushings are not causing a 'clunk'. When I actually had a clunk you could feel in the floorboard, I had a broken tranny mount. It felt the EXACT same way...felt like someone hit the floorboard with a rubber mallet. That took 6+ months to find since I kept snooping around in the rear end.

My RTAB's were shot, and I still didn't have a 'clunk'. The only thing suspension wise that might have been considered as a clunk, was worn out control arm ball joints. I didn't notice them when I replaced my RTAB's so I was able to isolate the problem.

My tranny mount is fine. Rear balljoints very well may have been the cause, I'm pretty sure they're still original, and the original rubber bushing style outer lower control arm bushing is in there currently, not a balljont...so that's probably original as well.

got all new balljoints and everything for out back...I'm just lazy and havent pulled the subframe out to do them all yet.

[Ace and Ivy M3]

Ok so I have a 96 M3/2/5

Im running UUC ltw flywheel w/m5 cluch
H&R Race w/ Bilsteins
I know my rear subframe has been reinforced.

Now what do you guys recomend for bushings?
Motor/ tranny/ rear end etc etc.

Something good and fairly priced, thank you!

[VaTechE36]

motor...I'm running vorshlag nylons in my race car...my street cars are running power flex in the front and rear and UUC Blacks with enforcers for the tranny.

[hoyabob2003]

I've got the AKG's - great quality pieces and no noticeable increase in NVH with substantial increase in rear end stability. Highly recommended.

[bmwpowere36m3]

I did PF Race "Black" Subframe bushings, so far so good. I did double up the washers and weld them together.