[Dr3K0]

I have search but have not find an answer for my question.

I need to know if I can use the entire rear differential (not the pumpkin) from an auto into a manual car??

Are they interchangeable??



thanks

Dr3K0

[tibra1]

So let me understand..you wanna spend a ton of money going from an open differential to an open differential?..

Uh why?

[scottp999]

PM Harold at HP Autowerks. I don't know about the 135. There was a change on the 335 with some different sizes. Harold knows every detail. People do put the auto ratio gears in manual cars, usually when moving to an LSD.

[skinrock]

Originally Posted by scottp999

PM Harold at HP Autowerks. I don't know about the 135. There was a change on the 335 with some different sizes. Harold knows every detail. People do put the auto ratio gears in manual cars, usually when moving to an LSD.

Pre 9/07 used a large pumpkin, which was the same as manuals, including the 135. After that it was switched to a small pumpkin, but the manuals stayed the same size if I remember correctly. For example, I know for a fact a pre 9/07 auto diff will fit on a manual 135 (full pumpkin swap).

Either way, it sounds like he just wants to use the internals (although it's worded oddly because he said entire rear diff, but not the pumpkin).

I second the notion to contact Harold at HPA, he knows everything and then some.

[pcockley]

Originally Posted by skinrock

Pre 9/07 used a large pumpkin, which was the same as manuals, including the 135. After that it was switched to a small pumpkin, but the manuals stayed the same size if I remember correctly. For example, I know for a fact a pre 9/07 auto diff will fit on a manual 135 (full pumpkin swap).

Either way, it sounds like he just wants to use the internals (although it's worded oddly because he said entire rear diff, but not the pumpkin).

I second the notion to contact Harold at HPA, he knows everything and then some.

for Harold what he doesn't know isn't worth knowing

[tscdennab]

Originally Posted by tibra1

So let me understand..you wanna spend a ton of money going from an open differential to an open differential?..

Uh why?

Simple, because the automatic differential has 3.46:1 gear ratio while the manual differential has 3.08:1 ratio so if you put the automatic differential into a manual car the car will accelerate faster (and have a lower top speed in each gear).

[VegasM2]

Yes you can. I did it to my car and I love it. I had it installed w my quaife LSD. When researching it I found someone who had done the calculations on the difference. Approximately a 12% increase in torque in every gear. It's a terrific mod. Only downside is a bit higher rpms at cruising speeds...about 400 higher w the 3.46 than w the 3.08.

[tibra1]

Originally Posted by tscdennab

Simple, because the automatic differential has 3.46:1 gear ratio while the manual differential has 3.08:1 ratio so if you put the automatic differential into a manual car the car will accelerate faster (and have a lower top speed in each gear).

Ok well then the OP expain it poorly..you can change the gearing..no need to get an auto diff.

check these guys out..they do it all day long.

www.diffsonline.com

[Dr3K0]

I meant what I said. I want to use the 3.46 gear on my car. I can install an lsd later or at the time of the swap. The thing is if I can just swap the entire differential from the auto into the manual equipped car. Otherwise I will have to ether hunt a pre 9/07 or pay big bucks.

At the power lever my car is now I don’t need the lsd yet. If I can swap an auto diff first and then when the power is max out and need traction, I will save for an lsd.

[Dr3K0]

Anybody knows the answer?

[HP Autosport]

Originally Posted by Dr3K0

I have search but have not find an answer for my question.

I need to know if I can use the entire rear differential (not the pumpkin) from an auto into a manual car??

Are they interchangeable??



thanks

Dr3K0

The entire differential is the pumpkin.

If you have a 135i as stated in your profile, then the answer is maybe. The auto diff is smaller dimensionally so you will also need to auto drive shaft.

[HP Autosport]

Originally Posted by M3Rob95

What do you mean by smaller dimensionally? Ie the input flange is smaller? Because I was under the assumption they were interchangeable.

Please advise.

Thanks

The overall dimensions of the final drive is smaller.

[Roger Castro1]

Originally Posted by VegasM2

Yes you can. I did it to my car and I love it. I had it installed w my quaife LSD. When researching it I found someone who had done the calculations on the difference. Approximately a 12% increase in torque in every gear. It's a terrific mod. Only downside is a bit higher rpms at cruising speeds...about 400 higher w the 3.46 than w the 3.08.

so just to confirm, I can get a whole used auto differential and replace my Manual differential on my 2009 e90 335xi, front and rear?? will this be a straight bold on? no other mods needed ???

I appreciate if you confirm