rear subframe/ trailing arm bushings

[The Dark Side of Will]

if you don't want to wear out your pinion bearings prematurely, yes.

I don't think the driveline angle will have ANY affect on pinion bearing wear. The loads on the pinion bearings from the diff gear mesh greatly exceed what it sees from the u-joint.

There *might* be a case for slight changes in diff angles causing premature wear to guibos, but I don't think that's anything close to a big deal either.

[The Dark Side of Will]

excellent, so the main thing is just lowering my diff about a quarter inch.. not terrible..!

I didn't realize what you meant by this... you're talking about putting spacers between the diff an subframe and keeping the stock iX diff mount to the body.
Yes, you can raise the subframe with RWD mounts, keep the diff where it is and shim between the diff and subframe.

That could work as long as there's clearance for the u-joint where the driveshaft passes through the subframe.

You *WILL* need a camber & toe kit to make this work. Whether that's eccentric trailing arm bushings or eccentric bolt/channel style adjusters doesn't matter.

I'd like to enlarge your thoughts before you do something stupid.

First of all, you know, the rear subframe is connected to rear diff. So there is actually 3 points that holds the rear end on. So if you lower the front bushings by using rwd bushes without extendion kit, you will bend the subframe upward. That changes the axle of your drive shaft and might worn out sooner or later.

Also, the movement at rear axle makes camber and caster to change. By lowering your rear axle your camber will be fucked up without any adjustable bushings. Mine has strong camber, but I dont care. Car gains so low mileage per year.. You can find the extendion kit dimensions from my build :) if you have anything to ask, hit me with message

The angles involved won't have any effect on driveline wear. The numbers are just too small.

Yes, the change in ride height will require adjustment to both camber and toe.

I have one of these kits on the shelf, but have not installed it yet:

http://www.e30tech.com/forum/showthread.php?t=80410

[nando]

I didn't realize what you meant by this... you're talking about putting spacers between the diff an subframe and keeping the stock iX diff mount to the body.
Yes, you can raise the subframe with RWD mounts, keep the diff where it is and shim between the diff and subframe.

That could work as long as there's clearance for the u-joint where the driveshaft passes through the subframe.

His car is lowered, so he doesn't need to worry about the camber kit. it will still be within spec, or close enough that tire wear won't be an issue.

there's lots of room through the subframe for this as well.

[The Dark Side of Will]

If he's lowered, then he's just going to stock(ish) RWD geometry. I have no idea why anyone lowering an iX would NOT go to RWD subframe bushings...

[nando]

yeah, exactly.

I don't think many people know. I only found out by accident after I already had them.

I agree that the pinion angle is unlikely to damage anything, but it's easy enough to space it down and there's definitely room, so I think it's worth doing anyway.

[imwhyteyo]

well.. im pleased to find out this turned out in my favor! thank you guys. im very happy about this.

[imwhyteyo]

as i tackle this job i realize the AKG bushings have an aluminum center sleeve, that i believe wont require the use of that top+bottom washer? will it change the angle any more if i DO decide to keep them? i like the idea of minimizing the vertical deflection, anybody have some thoughts on this?

edit: after an email with AKG they say it is not required, though, as ive said i think it wouldnt hurt to keep it. give me your two cents!!

[ScHpAnKy]

I'm looking at doing the something similar -
As i understand it, if I order the AKG poly RWD kit, I have to add 1/2" spacers where, exactly? My iX is lowered on H&R / Billies

What happens if I order the RWD kit but substitute the RWD subframe bushings for the iX-specific AKG ones?

[nando]

Between the diff and subframe

[The Dark Side of Will]

AWD: http://www.realoem.com/bmw/showparts...13&hg=33&fg=30



04 PUSH ROD LEFT 1 33321128679 $41.35
04 PUSH ROD RIGHT 1 33321128680 $41.35

RWD: http://www.realoem.com/bmw/showparts...13&hg=33&fg=30



04 PUSH ROD LEFT 1 33321124465 $41.35
04 PUSH ROD RIGHT 1 33321124466 $41.35

If you're lowering, just get these and bolt together like a straight RWD suspension ;)

You'd either space the diff from the subframe or modify the body mounting ear to raise the diff mount by the same amount you raise the subframe.

[FastAndLight]

If he's lowered, then he's just going to stock(ish) RWD geometry. I have no idea why anyone lowering an iX would NOT go to RWD subframe bushings...

Sorry, I thought I was following, but now I'm confused.

Lowered car should just use the normal RWD subframe bushings or should a lowered car use the RWD bushings + 1/2" spacer between diff and subframe?

Thanks for breaking it down. I just realized that I bought RWD subframe bushings, but my car is lowered so I'm just trying to make sure it is right(ish).

[nando]

you use both. the spacers just reset the diff to the correct location.

[The Dark Side of Will]

The spacers reset the diff to the AWD location. The diff mounting ear on the AWD body puts the diff at the right height for the AWD subframe height.

If you raise the subframe, then the diff ends up tilted. You could either mod the diff mounting ear on the body (e.g. by going to the E36 dual mounting ear setup) to put the diff in the RWD location, OR space the diff from the subframe to keep the diff in the AWD location.

[FastAndLight]

The spacers reset the diff to the AWD location. The diff mounting ear on the AWD body puts the diff at the right height for the AWD subframe height.

If you raise the subframe, then the diff ends up tilted. You could either mod the diff mounting ear on the body (e.g. by going to the E36 dual mounting ear setup) to put the diff in the RWD location, OR space the diff from the subframe to keep the diff in the AWD location.

Sounds good. So, 1/2" washers with the RWD sub frame bushings will put everything in the right spot. Thanks for the help.