[sonorous]

I recently installed new springs and dampers and replaced the strut bearings or as BMW calls them, "guide bushings". I have a 2007 E90 335i with OEM sport package (not X-drive). Looking at RealOEM, and many threads here, I ordered the new strut bearings under P/N: 31306775098.

When I took out the old bearings, I was surprised by how different they looked. The photo below shows the new part on the left and then old on on the right. I checked the P/N's on the part and the old number was: 31336775098. I looked everywhere and I could not locate this part online. The only other number is the non-sport part which is: 31336760943. I have read that that part is even taller than the "098" version.

You can see from the pic that the new bushing is quite a bit taller. I measured them with dial calipers and they were:

new: 3.05"
old: 2.70"

This meant that the new part was 0.35" taller. I was quite concerned that I would get weird lowering results but took the plunge and went with the new part.

My pre and post spring measurements showed that I was about 1.1" lower in front. And this is coming from sport suspension remember. I am very happy with this drop and would not want it any lower.

In researching spring/shock combos I came across a few posts of people describing more aggressive lowering than expected or at least different than other cars. At the end of this I could not help but wonder that this difference in strut bearings could be at least part of the conflict.

If anyone had a similar experience or can provide more facts I would be curious. Or maybe this information can help someone else in a similar situation...



This is the final stance for those interested:

[AlanAZ]

I had a similar experience:

http://www.e90post.com/forums/showth...ch#post9535385

I did double check the new part number later, and it is the correct for a later model 328i with sport suspension.

[Fork!TheSpoonWrecker]

Wait a sec, the longer perches lowered your car?

Originally Posted by Fork!TheSpoonWrecker

Wait a sec, the longer perches lowered your car?

What do you mean by "longer perches?"

Also, most all of the above info in this thread has been superseded and can reasonably be discarded.

[thakid22]

There are three mount versions available for the E9x.
Base Suspension mount. Sport suspension mount. M3 Mount.

The base and sport mount are interchangeable. Initially, BMW specs a specific mount for Sport suspension vehicles. This mount featured heat treated metal surfaces (for strength).
I do not know if the durometer of the rubber was any different. Later in production, BMW started using the base suspension mount on all non M3 E9x to save cost.

Now, looking at the OP's photos above... The difference shown is due to wear, not design. The mounts start off tall and domed. But after you install them they get compressed and flat at the bottom (top in the photo as they are upside down there). Don't be alarmed at the difference in height between new and old. But be aware that new mounts will initially make the front end sit a bit higher until they have broken in to their natural position. This doesn't take long at all.

[agustincuenca]

how many miles on the old strut mounts? that actually looks like worn rather than a different part number or different build.... actually what is lower is the rubber portion of the part....


love the wheels BTW....

[Fork!TheSpoonWrecker]

sorry i ment longer strut mounts = lower ride height? i dont see how that would make sense. Yeah i get the whole new vs old i just couldnt wrap my head around something being longer making the right height lower. I do have the updated ones on my car also but looking for other ones as they've gone bad after 6 months. they were Lemfoerder branded was trying to figure out if m3 ones did fit but i think they hit on the upper spring perch.

[matteblue3er]

This is completely normal. As the top hat bushing ages, it sags.

Originally Posted by Fork!TheSpoonWrecker

sorry i ment longer strut mounts = lower ride height? i dont see how that would make sense. Yeah i get the whole new vs old i just couldnt wrap my head around something being longer making the right height lower.

All a "longer" perch does is create a deeper pocket for the spring to sit in. Since OEM E30 perches are shallower than stock, they do the opposite, which results in an increase in ride height.

Think of it this way; if you dig a 1 ft hole in the ground and stand in it, you have effectively "lowered" your height by 1 ft relative to "stock" ground level. If you get out of the hole and stand on a 1 ft box, you have "raised" your height relative to ground level. Same concept with spring perches; ride height change comes as a result of which depth perch you end up choosing in contrast to stock E9x perches.

[Fork!TheSpoonWrecker]

but the thing is, the the spring doesnt attatch to the upper strut mount, if it did id understand your point. the strut mount then add an .3" on top of what it already is. ive seen ppl raise the car by sticking a metal place in between the strut mount and the mounting point on the car to increase the height..

[2fast4]

Hey guys, I'm about to do the strut mount replacement along with coilover install.
Then I came across confusing part about the strut mount.
I ordered and received Lemforder 31336752735. I didn't see that it has to be prod date 6/2008+. My car prod date - 9/2007.

I took out the original mount - 31336775098. Now superseded by 31306775098.
Looking at both, I can't tell the difference other than the taller new mount on the rubber dome which will flatten once installed.

The new Lemforder is made of aluminum being non-magnetic and much lighter.
My original mount is steel and magnetic, heavier.

So what's the difference? Can I install the 31336752735?

[feuer]

@2fast4 yes you can. Go ahead. Install.

[2fast4]

Originally Posted by feuer

@2fast4 yes you can. Go ahead. Install.

Thanks

[The Nightman]

Originally Posted by 2fast4

Hey guys, I'm about to do the strut mount replacement along with coilover install.
Then I came across confusing part about the strut mount.
I ordered and received Lemforder 31336752735. I didn't see that it has to be prod date 6/2008+. My car prod date - 9/2007.

I took out the original mount - 31336775098. Now superseded by 31306775098.
Looking at both, I can't tell the difference other than the taller new mount on the rubber dome which will flatten once installed.

The new Lemforder is made of aluminum being non-magnetic and much lighter.
My original mount is steel and magnetic, heavier.

So what's the difference? Can I install the 31336752735?

Not sure if this matters but RealOEM shows no E9x applications for 31336752735 despite looking the same:

https://www.realoem.com/bmw/enUS/partxref?q=31336752735

I think I would try to get 31306775098. It's a beefier mount for E9x vehicles with Sport suspension:

https://www.realoem.com/bmw/enUS/partxref?q=31306775098

[2fast4]

Originally Posted by freedomfries

Not sure if this matters but RealOEM shows no E9x applications for 31336752735 despite looking the same:

https://www.realoem.com/bmw/enUS/partxref?q=31336752735

I think I would try to get 31306775098. It's a beefier mount for E9x vehicles with Sport suspension:

https://www.realoem.com/bmw/enUS/partxref?q=31306775098

Chasing after the p/n for this is about to go federal court.
There are p/n from many different sellers and we have nothing but confusion...Some sellers list obsolete p/n while others list new p/n. Some of them will list obsolete + list new p/n. Then some has odd p/n like W0133-1662946-LEM Lemforder brand. Is it in the RealOEM? Heck no.

So far this is what I know...31336752735 replaces obsolete 31336760943(aluminum I believe). Both are of same, but sellers list the obsolete 31336760943. The one I just bought which I need to return = W0133-1662946(also alum). I believe they both are same. This number might be Lemforder p/n.

Then there is new 31306775098 which replaces obsolete 31336775098.
This is heavier duty with heat treated steel shell. You can see by the darker color and some red hue in it. This is what OP also described.
Lemforder p/n also is W0133-1779570.
This is also more pricier than the previous mentioned.

So I'm settled on ordering the 31306775098. Before 6/2008 prod date.
I put the W0133-1662946/31336752735/31336760943 up on the holes to see if they mate up. It fits exactly like the stock...small appearance variations do exist between the 2 but minor.

So in big picture, there are 2 kinds. 31306775098 and 31336760943 according to year before 6/2008 or after, and some degree of sport or non-sport models.

[BryanH]

This thread has the best title so I am posting here for future search engine results.

My quest led me all over the place, but I believe I'm coming to the same conclusion, eventually, that the Lemforder 31 30 6 775 098 may be the correct upper strut mount for an LCI 328i sedan with M-Sport suspension package (S704A).

My confusion began when placing an order for Bilstien B4S replacement dampers from FCP Euro. Wanting to replace all the accessory mounting rubber and bump stops at the same time, I kept adding these things to the order but couldn't find an upper strut mount that was correct for my car (a 2011 328i RWD sedan with sport package). After much searching and cross referencing, I am beginning to think their web site may not be fully correct regarding the fitment information for this part.

ECS Tuning (and other sources) seem to have more generous and general fitment inclusion lists. While the "098" Lemforder mount is said to fit, I want to be sure I'm getting the correct part.

I went to the best source I could find: ZF (parent company of Lemforder and Sachs, among others). Drilling down in their WebCat online catalog, I landed on a page which I can't direct link so I'll include a screenshot:



[Item #18 is the part in question]

I interpret "for vehicles with M-technology" to mean M-Sport suspension in this case. So the correct part should be this one, which shows the BMW part number 31 30 6 775 098 as well as a Lemforder part number 31211 (or 31211 01). ZF's page for this part shows it as being suitable for standard suspension cars up to June 2008 production as well -- early sport suspension cars got something different yet? I digress.

FCP Euro's page for "the 098" does cross reference Lemforder P/N 3121101 but their fitment list doesn't match ZF's exactly. A more comprehensive review of FCP Euro's fitment chart shows that it's listed as correct for several E9x iterations with the S704A suspension package, yet for 328i sedans only 2008 is listed there. I believe this may be an omission.

I hope I am correct and that this may help others avoid a similar headache in the future. If I do find that I'm right I'll contact FCP Euro to let them know. I wonder if I will find a part number on the original strut mount when I remove it. I'll sleep on it but I plan to order "the 098" soon and I'll report back my findings, if any.

I welcome any factual or first-hand corrections (internet heresay isn't my favorite source if I'm honest!).

[Tambohamilton]

https://translate.googleusercontent....xdc-ERZjDxBmvA