Open or LSD 3.91 in my '72? Got a worn out LSD, and have been posed with this question. Could acquire an open one for $200, or a LSD for almost $900. Anyone got an opinion with good justification? Look for the ups and downs.

Regards,
Chris

Who ever is selling those diffs is on crack. The prices are crazy. I puchased an LSD done by Jack Fahuna last year for 250 bucks. You need to find a nice pick and pull.

The $900 3.91 LSD is completely rebuilt, and that price is close to what I have seen on the internet. That does seem fairly high though. But what I am getting at is the advantages/disadvantages to both when compared against one another.

Chris

Hello,

Yeah those are pretty crazy prices. I had my 4.10 lsd installed in my 318is for a total of $350..speaking of which.

I have the 4.10 open diff for sale if you're interested I see that you're local and I'm only looking for $75 picked up. There's nothing wrong with it, let me know via pm, thanks!

Jon Mills

Thanks for the input. I think I am going to stick with 3.91. Would that 4.10 fit? Thats a great price, if I go in another direction, I will keep you in mind. Anywho, I would still like the answer to the original question, lsd or open? regardless of price...lol.

Chris

lsd for sure. 900 is crazy. ive seen them for 300. used though

lsd for sure and wow i need to sell some parts!

Yes the 4.10 should fit, 318's got the smaller diff just like 2002s. In fact my mechanic (Mike Robinson) told me to keep it because a lot of 2002 guys love to swap out theirs for the shorter gears of the 4.10. Let me know I live in Chesapeake (Great Bridge) so it shouldn't be a far drive to get it.

Yes the 4.10 should fit, 318's got the smaller diff just like 2002s. In fact my mechanic (Mike Robinson) told me to keep it because a lot of 2002 guys love to swap out theirs for the shorter gears of the 4.10. Let me know I live in Chesapeake (Great Bridge) so it shouldn't be a far drive to get it.

My '72 is at Mike's shop as we speak, ironically. I will speak with him tommorrow and see what he says.

Chris

4.11 5 spd and an S 14 tear it up!!

I have a 4.10 diff in my 1600 (w/ 2.0L motor) and it is quick, quick, quick. Now it is true that some of the quickness is due to the lighter car, but still, I am sure the ratio makes a noticeable difference. It does wind the motor up at highway speeds (w/ a 4-speed).

Between open and LSD, I would get LSD. In fact, I have an LSD swap waiting for me to find the time to install.

My '72 is at Mike's shop as we speak, ironically. I will speak with him tommorrow and see what he says.

Chris

Wow what a small world, haha. Yeah he was the one who sold me the 318 and installed the diff on there for me. Obviously an lsd would be better than an open diff but I'm selling mine real cheap because I don't want it to just sit in my garage etc. You can tell him its from Jon Mills if you'd like, he'll know exactly what you're talking about.