Rear Axle Codes

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Dec 17, 2019 | 04:53 PM

63flareside

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Tuned

Joined: Dec 2011

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From: South Dakota

Rear Axle Codes

Anybody able to tell me the gear ratios of codes 25, aswell as 29 on an F350. Checking gear ratios on a possible donor for my 61 F350

Dec 17, 2019 | 05:16 PM

TA455HO

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From: Seattle

Quote:

Originally Posted by 63flareside

Anybody able to tell me the gear ratios of codes 25, aswell as 29 on an F350. Checking gear ratios on a possible donor for my 61 F350

For 1961/62 a code 25 is a Timken B140 in a 4.86 ratio and a 7,200 lbs axle capacity and a 1961/62 code 29 is a Dana (Spicer) 70 in a 5.87 ratio and also 7,200 lbs rated capacity. Both non-locking.

Dec 17, 2019 | 05:34 PM

63flareside

Thread Starter

Tuned

Joined: Dec 2011

Posts: 373

Likes: 65

From: South Dakota

thanks for the reply, found a 65 napco with the 29 code but my 61 is a 25 code. looking at a couple different options, the 65 is a dually but I want to keep my 61 a srw, the 65 axle is pretty far in the ground and worried the rear end will not be salvageable, my 2 options would be to see if I could regear my timken B140 to 5.87 or rebuild the dually rear end if it will work with SRW's

Dec 19, 2019 | 03:36 PM

1960fordf350

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From: parma

Why would you want a higher ratio? You would gain pulling power but lose top end speed. I have a b140 pig with 5:83 ratio sitting in my garage. I'd be up for the 4:86 ratio for my truck. But I thought the ratio for that axle was 4:88. I have the 5:14 in my axle right now.