D30 ratio's and 2.5L's

[Jeff in VA]

In the process of converting my MJ to 4WD and made an interesting discovery...I got a D30 from an identical '87 MJ 2.5L to swap into mine and the R&P is 3.55. I "thought" the only two possible stock ratios would be either 3.73 or 4.10 (which my MJ rear is) . Anyone else out there seen stock 3.55 gears in a 2.5L MJ or XJ? The only thing I can figure is that the donor truck is from the south (VA).
Check my ad on the For Sale board...I need a 4.10 D30 to complete the conversion and am looking to either swap or sell the one I have w/ 3.55's.
Thanks!
Jeff

 

[Eagle]

I've posted this several times, I guess you missed it. Ratios with the 2.5L were all over the map in the early years, depending on what tranny you got, with or without tow package, and in the case of the manual trannies, whether it was 4-speed or 5-speed.

I have a 1988 2.5L 4-speed out in the yard with 3.55 gears. I expected 3.73s, but since the 4-speed doesn't have an overdrive you can sort of see whay they didn't put as much gear in it. Mine's a 2WD from Massachusetts.

In the later years Chrysler pretty much made all the 4-cylinders with 4.10 gears, but I don't know when that started. In the early years, available ratios were 4.10, 3.73, 3.55, and 3.31.

LOOK BEFORE YOU BUY if you're shopping for 4-cyl axles.

 

[Jeff in VA]

Now that you mention that, I do remember the donor MJ being an auto, I think. Oh well, it's a fun project so far, and if this is the worst that happens I'll be happy
BTW, if I had to, would it be possible to swap the R&P with a 4.10 set, or are the carrier sizes different? I have a shop local that I would trust to do an install but forgot to ask them when I was in town. Gears really ain't my bag, yet....
Jeff

 

[Eagle]

I don't remember where the carrier break is for the D30, but I know there is one. I think you need a new carrier to jump from 3.55 to 4.10.

 

[Jeff in VA]

I've confirmed it, the carrier break is 3.55 (just my luck...) Thanks for the info, Eagle.

 

[Ghost]

Uhh Jeff I have a 3.73 front and rear coming availabel soon. You intrested in some Hog trading? [email protected]

 

[Ghost]

Oh by the way my FSM says the 3.31 were in the "Fuel economy package"!