I pulled a diff from a friend's 533i parts car yesterday. Tagged as a 3.25 LSD but he had to swap the rear covers to fit what he said was a diff from a 635 to the 533i years ago. I checked it by rotating and it did get 3.25 turns on the input for one on the output flanges, and it is an LSD so maybe the tag is correct. So I pulled mine, swapped covers, and tried to put it back in. Everything lines up fine except for the two upper bolts in the rear axle carrier. I see from RealOEMBMW that there is a break in the rear axle carrier part number from 9/82 so I've asked my friend to check production date on the 533i just to confirm if that might be a factor. Otherwise, I'll go back at it in the light of day. Anyone else been there, done that and can offer some advice? Looks like it may require drilling two new holes in the top of the diff carrier.
The old diff (3.25 LSD) out of my new '87 535is is SOOOO noisy it's rough even spinning it out of the car. And the pickup for the speed sensor was covered in bearing mud. This with careful service records since new and mainly Red Line diff oil. Hmm.
Thanks for any help, condolences, or offers of cheap new diffs (one daughter in college, two more to go still!). I'll let you know what I find tomorrow if it doesn't snow.
-Phil
Help with diff swap from 533i to 535i. Should it fit?
If this is your first diff swap, you must get the upper most bolts started before the front ones, otherwise if you leave them for last it is very difficult with the front ones threaded. If the holes seem about 1/2 inch off then this is probably your problem. Same issue I ran across when swapping my differential.
Not familiar with diffs to know what was changed in production, most likely the break was from the 533 to 535i in late '84. The break in '82 was from the early E28 run. But I thought from late '82 most of the mechanical bits were the same.
Not familiar with diffs to know what was changed in production, most likely the break was from the 533 to 535i in late '84. The break in '82 was from the early E28 run. But I thought from late '82 most of the mechanical bits were the same.
As it happens it is my first diff swap...well, at least my first one lying on my back on a piece of plywood on a gravel driveway. Call me spoiled, I'm used to lifts! Thanks for confirming that. I did save the top ones 'til last. Hooked it on the driveshaft loosely first with it still supported on a floor jack, then hung the back bolt in the rubber block, then the front two, not snug, then it was too dark to figure out what was happening. I thought I'd check before pulling it all back out and feeling really foolish when it matched up fine with the old one.
I did check the VIN on the donor car and it's 10/83 production and RealOEM shows the same diff carrier for that and my '87 so I'll hit it tomorrow with renewed fervor and confidence gained from your suggestion. And I've added a nice 16mm wrench to my collection, filling a void I never knew I had! Yeah, I know SAE would work but it just ain't right.
Thanks,
-Phil
I did check the VIN on the donor car and it's 10/83 production and RealOEM shows the same diff carrier for that and my '87 so I'll hit it tomorrow with renewed fervor and confidence gained from your suggestion. And I've added a nice 16mm wrench to my collection, filling a void I never knew I had! Yeah, I know SAE would work but it just ain't right.
Thanks,
-Phil
It was either MY 84 or MY 85 that the rear diff mount changed. The earlier style -- 533i, etc -- has a centered rear diff mount whereas the later style -- 535i, etc -- has a diff mount offset to the left. If the casings are the same, you can just trade out the covers.
As it turns out, I bought a 3.45 diff -- yes, 3.45, not 3.46 -- off of an E28 Euro '82 528i, and the diff was completely different. I couldn't even swap the covers. So, JBort has it on his car now! It was an interesting diff.
Anyway, if the casings are the same, swap out the covers, and you're good to go.
HTH,
As it turns out, I bought a 3.45 diff -- yes, 3.45, not 3.46 -- off of an E28 Euro '82 528i, and the diff was completely different. I couldn't even swap the covers. So, JBort has it on his car now! It was an interesting diff.
Anyway, if the casings are the same, swap out the covers, and you're good to go.
HTH,
Thanks but that's not the problem. You're right, the earlier diffs have the rear bolt into the rubber silentblock centered, the later is offset to the driver's side, but I already swapped the rear covers. This problem is with the two upper bolts that go directly into the cast iron case from the rear axle carrier and here I think Justin's got the answer. I'll know tomorrow.Shifty wrote: Anyway, if the casings are the same, swap out the covers, and you're good to go.
Thanks for trying to help.
-Phil
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canyoncarver
- Posts: 1123
- Joined: Feb 12, 2006
justin is right..and theres definitely a trick to swapping difffs,...............if youve got a lift...you can r&r a diff in 20 minutes.........and yes...........i have.
anyway..........hang the diff leaving the d/s bolts inserted but not secured by the nuts.
loosely thread first the forward diff bolts, then the rear. once al l are loosely threaded... tiighten them using a ratchet. once all are snug.....lift the diff and tighten the main diff mount on the rear cover.
lastly...secure your d/s............
might wanna use a floorjack to support the diff..beats using your arms or back..........
anyway..........hang the diff leaving the d/s bolts inserted but not secured by the nuts.
loosely thread first the forward diff bolts, then the rear. once al l are loosely threaded... tiighten them using a ratchet. once all are snug.....lift the diff and tighten the main diff mount on the rear cover.
lastly...secure your d/s............
might wanna use a floorjack to support the diff..beats using your arms or back..........
Phil,
Argh, that's what I get for speed-reading a post! I just caught the part about you swapping covers. My fault!
Getting all four bolt holes to line up on the subframe is the hardest part of installing a diff. The more easily you can make it to move the diff around, the quicker you'll get the holes lined up. Jim offers some great advice. Hopefully, I'll have little trouble installing my 3.46 in a few weeks since I plan on using a lift.
Argh, that's what I get for speed-reading a post! I just caught the part about you swapping covers. My fault!
Getting all four bolt holes to line up on the subframe is the hardest part of installing a diff. The more easily you can make it to move the diff around, the quicker you'll get the holes lined up. Jim offers some great advice. Hopefully, I'll have little trouble installing my 3.46 in a few weeks since I plan on using a lift.
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Steve Haygood
- Posts: 1943
- Joined: Feb 12, 2006
- Location: Thomaston Ga
- Contact:
[QUOTE="dworthy"]Not to rain on your party Shifty, but the euro 528i came with a 3.25 just like the 535i, it was the euro 525i that had the 3.45 diff.[/QUOTE]
My bet is that the 3.45 was an option on the 528i in the same way that the 3.73 was an option on the Euro M635CSi in lieu of the 3.91 that came on the US cars.
Either that or the 3.45 that came off of the '82 528i wasn't original. Either way, I gurarantee you it was a 3.45.
My bet is that the 3.45 was an option on the 528i in the same way that the 3.73 was an option on the Euro M635CSi in lieu of the 3.91 that came on the US cars.
Either that or the 3.45 that came off of the '82 528i wasn't original. Either way, I gurarantee you it was a 3.45.
It was amazing; that euro 3.45 bolted right into a stock '83 528e chassis! I didn't change a thing!
I believe it's the perfect ratio for a 5-speed eta!! (With the 3-sp. auto w/o overdrive, I was limited to 85 mph...Then came the 5-speed conversion that gave "Shifty" his name! Then the full cosmetic euro conversion...).
Thinking back on it, I think the 3.45 diff came from an '81 528i, not an '82! It was still an E28, though, as the Euro cars changed over for MY 81.
Jay, that was one funky looking diff, wasn't it? I've still never seen one like it. Not a sideloader. Not a big diff. Not a standard E28 diff. WTF is that thing?!
I agree with you on the diff ratio. 3.46 is perfect for a 5-speed eta. I loved it on my blue 528e and can't wait to get the one in my friend's garage on my car!
Jay, that was one funky looking diff, wasn't it? I've still never seen one like it. Not a sideloader. Not a big diff. Not a standard E28 diff. WTF is that thing?!
I agree with you on the diff ratio. 3.46 is perfect for a 5-speed eta. I loved it on my blue 528e and can't wait to get the one in my friend's garage on my car!
Well, thanks to the suggestions from you guys, everything worked out fine. I loosened up all the mounting bolts, leaving only two nuts threaded about three threads on the driveshaft. It's actually amazing how much flex there is in the rear axle carrier. I got the upper/rear bolts in loosely and let the diff hang to line up the front two. With all four bolts in the casing the rear mount was about 3" from being in up high enough so the floor jack took care of the rest. Very critical to have a functioning rear rubber mount with as much flex as their is in the back axle. I'd call it flimsy but then it can't be; it's a BMW!
But that wasn't the end of the story. I couldn't get the inside CV joints to seat in the diff output flanges properly. I kept thinking if I cranked down on them they'd line up, but stopped before messing anything up and measured the flanges on the removed diff. Larger machined surface inside the old flanges to accept the CV joint covers! So, unbolt the half-shafts again and swap flanges. But then everything worked just fine. The test drive was worth it. The world's noisiest diff was replaced by the sound of a perfectly functioning BMW.
It was sure worth it, especially since the only cost was my worthless labor. Thanks for everyone's help and suggestions or I'd still be out there pulling the diff back out to drill the axle carrier!
-Phil
But that wasn't the end of the story. I couldn't get the inside CV joints to seat in the diff output flanges properly. I kept thinking if I cranked down on them they'd line up, but stopped before messing anything up and measured the flanges on the removed diff. Larger machined surface inside the old flanges to accept the CV joint covers! So, unbolt the half-shafts again and swap flanges. But then everything worked just fine. The test drive was worth it. The world's noisiest diff was replaced by the sound of a perfectly functioning BMW.
It was sure worth it, especially since the only cost was my worthless labor. Thanks for everyone's help and suggestions or I'd still be out there pulling the diff back out to drill the axle carrier!
-Phil
[QUOTE="a"]not only that, DIY has the advantage of fitting into your schedule, not changing yours to suit someone elses. [/QUOTE]
[QUOTE="Shifty"]Unless your car is your DD!
[/QUOTE] it is,, The Borman6 has always been very co-operative in choosing its moments to act up. Major repairs have always been performed at a time of my choosing. I guess I'm a good enough shade tree hack to fix stuff before it totally fails. Plenty o time to shop for parts and plan out job. Next one is a timing belt -ectomy/ water pump in early May . when it hits 300k , maybe a cake with candles.
[QUOTE="Shifty"]Unless your car is your DD!
[/QUOTE] it is,, The Borman6 has always been very co-operative in choosing its moments to act up. Major repairs have always been performed at a time of my choosing. I guess I'm a good enough shade tree hack to fix stuff before it totally fails. Plenty o time to shop for parts and plan out job. Next one is a timing belt -ectomy/ water pump in early May . when it hits 300k , maybe a cake with candles.