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DISCUSSION => Engine + Driveline => Topic started by: g0dspeed on September 20, 2007, 04:03:13 AM

Title: Changing the rear diff
Post by: g0dspeed on September 20, 2007, 04:03:13 AM

I'm thinking of changing the rear diff on my ride... currently i'm running on a 4:10 diff... n i'm thinking of changing it to a smaller ones... any suggestions/experience???

thanks guys...

Title: Changing the rear diff
Post by: Wise Old Dog on September 20, 2007, 05:47:54 AM

I've got a 3.91 in mine. Seems to be just as quick as the 4.10, but about 300 less RPM at highway speeds. I don't think I would go with any other gear though, unless most of your travels are on the highway.

Title: Changing the rear diff
Post by: b318isp on September 20, 2007, 07:33:24 AM

Quote from: Wise Old Dog;34048

I've got a 3.91 in mine. Seems to be just as quick as the 4.10, but about 300 less RPM at highway speeds. I don't think I would go with any other gear though, unless most of your travels are on the highway.

When you mean smaller, do you mean short or longer? Unless you have a specific reason to change, then leave it alone. Only active recommendation would be to fit a LSD.

Title: Changing the rear diff
Post by: tjts1 on September 20, 2007, 07:32:53 PM

I went from 4.1 to 3.64 and I'm very happy with the results. I just wish my 3.64 was also an LSD like my 4.1 Come to think of it, I could probably swap the LSD over. HAHA! Heres all the ratios that matter.
 http://www.m42club.com/forums/showpost.php?p=26477&postcount=28

Title: Changing the rear diff
Post by: silverblades181 on September 20, 2007, 08:26:48 PM

The lower you go in the gear ratios the less torque you have. It'll also take longer for your engine to reach it's already high powerband. So unless you have a close ratio transmission...personally I wouldn't go lower but higher like a 4.27.

Title: Changing the rear diff
Post by: g0dspeed on September 20, 2007, 11:04:54 PM

Quote from: Wise Old Dog;34048

I've got a 3.91 in mine. Seems to be just as quick as the 4.10, but about 300 less RPM at highway speeds. I don't think I would go with any other gear though, unless most of your travels are on the highway.

... a better top speed i presume?