New e34 but needs new Diff

[89535i]

Hi All,

I am the proud owner of a 89 535i 5spd. Its a great car. I had a 87 535i about 2 years ago, but I had to sell because at the time I needed a year round car, and the New England winters made it impossible to drive in snow. The growl of the m30 engine has haunted me ever since, so i gave in, and bought an e34..... =)

The car however will need a new differential. There are so many to choose from, and I'm not knowledgable as to what will fit, and what will not. So my question is, which differentials will fit me e34 5spd? There are people on ebay selling diffs from 325is's and say that they will fit a 535, but just not too sure if that will conflict with the gearing of the tranny. Any help will be much appreciated.

Thank you!

[ArtemLepilov]

All E34 differentials are interchangeable. You are better off with a posi-traction LSD if you have a manual. How do you figure that it needs a new differential? Is it whining?

In any case, on www.car-parts.com you will be abel to find many cheap ones - as low as about $100-150

-Artem

[Kalevera]

All E34 differentials are NOT interchangeable.

Some use large housing units, others use mediums. A 535 uses a medium housing.

Furthermore, the flanges are different, beyond the inherent changes between large and medium cased units. All are relatively easy to swap, but incorrectly loading the pinion nut (even the TIS spec is wrong) typically destroys the differential.

I can practically guarantee that I've worked with more differentials than anyone else on .info. Most units from junk yards are just that -- junk. Cars are typically not brought in on a flatbed. Sitting around in muck for years is not good for bearings and gear sets. Most higher mileage limited slip units have weak or bad clutches.

I wouldn't buy a used differential without being able to test drive the car prior to pulling it. There's a reason why we charge a grand and change for a new unit, including a good, long warranty.

best, whit

[Rigmaster]

Like Whit says, besides gear ratio + LSD or open, you have to make sure you get the correct size diff and the correct input flange type.

I disagree however with the opinion that used BMW diffs are probably junk. Whit may have installed more diffs than me, but I'll wager that I have removed more diffs than him... :) I have bought and sold many BMW diffs over the years, and only a few that I have sold- maybe 3 or 4, were in anyway "bad"- and 2 of those were suspect to begin with as they came from flood cars and had water in with the gear oil. The rest of them were A-OK. Keep in mind that you would be smart to install new side seals and rear cover gasket for sure, and get a new front (pinion) seal if there is evidence of a leak there, or if you need to have the input flange changed.

You need a diff from any E34 5 series except 540i or M5 to fit your 535i- these will all be the proper case to be a direct bolt-in. You could also use an E32 7 series diff from a 735i/il (but not 740i/il or 750i/il as they use the large case). The front (input) flange for your 5 speed 535i should be the same in any other E34 5 speed, as well as the 7 series cars- they should have the the larger 5 speed input flange, so they would bolt right in. There are exceptions to this, so be careful what you buy, and ask lots of questions. If the seller can't or won't answer your questions, you might want to move on to someone else, or take a risk that you're not getting the right part.

FWIW- car-part.com is notoriously inaccurate in their listings, it's basically a service that junkyards subscribe to to get their inventory listings online. I can tell you from firsthand knowledge that most junkyards do not take the time to check their diffs to make sure of the ratio or if it's LSD or open. They usually just put whatever description they can come up with- regardless of what it says on the diff tag!!


Bret.

[Kobe Diesel]

If you dont mind paying $500 and up, check Metricmechanics or Korman for rebuilt diffs.

[mholbrook]

I bought a 3.64 LSD for my last 535 and it seemed to me to be the perfect ratio for that car. (5 speed manual trans) I might be tempted with a 3.73 but anything steeper makes first gear useless. With the 3.64, you get just a hint of overdrive in 5th, I think about a 6-7 percent difference between the 3.46. Mine came out of a 750 and we had to swap the imput shaft. Guessed at the torque but it was working fine while I had it and the new owner has said nothing bad. Maybe we got lucky and got real close on the torque.

[89535i]

All E34 differentials are interchangeable. You are better off with a posi-traction LSD if you have a manual. How do you figure that it needs a new differential? Is it whining?

In any case, on www.car-parts.com you will be abel to find many cheap ones - as low as about $100-150

-Artem

The differential is whining on diff. I had it on the lift, put it 2nd gear then 4 gear, ran it to about 4K rpm and the whine was pretty bad.

I did however ran into some more recent problems. The power steering pump is whining, looks like smaller hose is leaking. Does anyone know if this is common?

Also, the clutch just recently started to become hard to push down. When the car warms up it gets better. When I had the car on the lift the shift shaft seal was leaking.

I brought the car to a mechanic this morning and he says that if it needs a new clutch I have to replace the flywheel also, is this true?

Anyhow, when the clutch gets really hard to put down, is this another common problem?

Any more help would be much appreciated.

[89535i]

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=8046901161&sspagename=ADME%3AL%3ARTQ%3AUS%3A1

??

[Rigmaster]

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=8046901161&sspagename=ADME%3AL%3ARTQ%3AUS%3A1

??


NO.



You need a diff from any E34 5 series except 540i or M5 to fit your 535i- these will all be the proper case to be a direct bolt-in. You could also use an E32 7 series diff from a 735i/il (but not 740i/il or 750i/il as they use the large case). The front (input) flange for your 5 speed 535i should be the same in any other E34 5 speed, as well as the 7 series cars- they should have the the larger 5 speed input flange, so they would bolt right in.

[89535i]

NO.
Ok, thank you. I was told that a 3.73 e30 LSD will fit in the 535i, is this correct? I believe just the flanges have to be changed.

[Rigmaster]

Ok, thank you. I was told that a 3.73 e30 LSD will fit in the 535i, is this correct? I believe just the flanges have to be changed.


I'm telling you- READ my original post.

If someone told you an E30 3.73LSD would fit your E34, they are wrong. If they just said that an E30 373LSD would fit a "535i", then they are correct, assuming the 535i is an E28.

Now, to confuse matters even more, the gears from an E30 373LSD (or any E30 6 cyl diff) WILL fit in an E34 diff case- but you need to know how to properly install + shim them- it's not a DIY job for the average DIY'er.



Save this part for your search- it's got pretty much all the info you need to know. E30, E28, E24, E23, E36 diffs will NOT fit in your E34.



You need a diff from any E34 5 series except 540i or M5 to fit your 535i- these will all be the proper case to be a direct bolt-in. You could also use an E32 7 series diff from a 735i/il (but not 740i/il or 750i/il as they use the large case). The front (input) flange for your 5 speed 535i should be the same in any other E34 5 speed, as well as the 7 series cars- they should have the the larger 5 speed input flange, so they would bolt right in.

[632 Regal]

lol, not an average job indeed, there are NO shim kits available for these differentials anymore, neither are new bearings.

the gears from an E30 373LSD (or any E30 6 cyl diff) WILL fit in an E34 diff case- but you need to know how to properly install + shim them- it's not a DIY job for the average DIY'er.

[89535i]

I'm telling you- READ my original post.

If someone told you an E30 3.73LSD would fit your E34, they are wrong. If they just said that an E30 373LSD would fit a "535i", then they are correct, assuming the 535i is an E28.

Now, to confuse matters even more, the gears from an E30 373LSD (or any E30 6 cyl diff) WILL fit in an E34 diff case- but you need to know how to properly install + shim them- it's not a DIY job for the average DIY'er.



Save this part for your search- it's got pretty much all the info you need to know. E30, E28, E24, E23, E36 diffs will NOT fit in your E34.

Thanks for your help. I read your post, but I wanted to see if anything else would fit, because I was not able to find one that would fit. Those I narrowed down my search with your help. Thanks!

[Kalevera]

Jeff, the shims part is on point, but the bearings are still obtainable. Timken is what we pull out, and what we install.

best, whit

[Rigmaster]

Thanks for your help. I read your post, but I wanted to see if anything else would fit, because I was not able to find one that would fit. Those I narrowed down my search with your help. Thanks!


Alrighty then!!

Didn't want to sound harsh- but I wanted to make sure you got the info correctly and understood it. :)

Any idea what ratio you are looking for?? I have a couple of OPEN E34 diffs available if interested- let me know.

Thanks!

Bret.

[89535i]

Hi All,

I am the proud owner of a 89 535i 5spd. Its a great car. I had a 87 535i about 2 years ago, but I had to sell because at the time I needed a year round car, and the New England winters made it impossible to drive in snow. The growl of the m30 engine has haunted me ever since, so i gave in, and bought an e34..... =)

The car however will need a new differential. There are so many to choose from, and I'm not knowledgable as to what will fit, and what will not. So my question is, which differentials will fit me e34 5spd? There are people on ebay selling diffs from 325is's and say that they will fit a 535, but just not too sure if that will conflict with the gearing of the tranny. Any help will be much appreciated.

Thank you!


Hey, I located a 90 535i diff. Its a 3.46 LSD unit. I bought it from Vines Auto motive in Alabama (US) and had it installed by Auto Technic in CT (US). Works great! Thanks for all the help.