MB / M38 compatability..

[charlesfitton]

Is it possible to swap out the rear diff from an M38/CJ2 and drop it in the floating axle dif in an MB/GPW?

...asking for a friend....

(Truth is - I donated a newer front dif to the project, and the tech didn't check the ratios as I suggested.
Now when it goes into 4wd, it winds up tighter than a bulls ass in fly season.

hoping that the easy fix is to drop in a read diff, too..)
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M38 CDN 52-30105
M38 CDN 52-30883

and other green crap...

[radtech]

I think you can put M38 diferentials in an MB if both front and rear are from the M38.

[charlesfitton]

Thanks - that"s what I'm trying to confirm...the front was already done, I'm hoping he can match the rear..
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M38 CDN 52-30105
M38 CDN 52-30883

and other green crap...

[wesk]

Charles are you asking about swapping the entire axle assembly from an M38 to an MB or just the differential.

M38:

Front: Spicer Model 25 5.38:1 Floater No steering bellcrank on it.

Rear: Spicer Model 44-2 5.38:1 Semi-floater. (axle retained in diff by outer bearing retainer)

MB:

Front: Spicer Model 25 4.88:1 Floater. Steering bellcrank mounted on axle housing.

Rear: Spicer Model 23-2 4.88:1 Floater (axle retained by flange bolts)

If you are only swapping the diffs then there should not be an issue so long as you truly have a Spicer 44-2 with 10 spline axle and not a later CJ spicer model 44 with the 19 spline axle. There is a slight difference in the inner axle bearing sizes and I do not recall what effect if any that has on the swap.

The side bearings at the diffs that support the inner end of the axles are:

MB Spicer 23-2: ORD# 705438, Timkin 24780

[charlesfitton]

Thanks - I was thinking that just the diff assembly would do it - should I ever try a job like that.

now I need to confirm that the diff did actually come from an M38, and not a CJ2 or 3.

Surprised to see that the ratio is actually higher on the M38, I expected it to be the other way round..

f
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M38 CDN 52-30105
M38 CDN 52-30883

and other green crap...

[wesk]

The WWII jeeps used 6.00-16 tires and the M38 used 7.00-16 tires. The tire diameter dictated the gearing change.

The 19 spline axles came much later than the CJ2A & 3A. Just look inside the diff's spider cage and count the receiver's splines. If they are 10 per side your good to go.
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Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

Mjeeps photo album: http://www.willysmjeeps.com/v2/modules.php?set_albumName=Wes-Knettle&op=modload&name=gallery&file=index&include=view_album.php