Dana 35 and 30 ratio question

That4.0Wrangler

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I swapped a Dana 35 into my jeep with a 3.07 ratio and the front diff is a 3.73 is it even possible for 4wd to work or will it grenade on me
 
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I swapped a Dana 35 into my jeep with a 3.07 ratio and the front diff is a 3.73 is it even possible for 4wd to work or will it grenade on me

giphy.webp
 
Seriously? Maybe you can run 225's in back and 33's up front.

Right?! There is probably a tire size that makes it work ok. And I guess if the surface is slippery enough then it might not grenade.

OR use an NP203 transfer case, which has a differential within it that you can lock/unlock.


See, lots of ways to make mismatched gear ratios work!
 
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Couldn’t find one with it but for now just won’t use 4wd I’ll re gear it soon

Found a good deal on that rear end and went with it

your going to have to replace your carrier too, to go from 3.07 to 3.73. I believe the break is at 3.55 on the 3.07
 
your going to have to replace your carrier too, to go from 3.07 to 3.73. I believe the break is at 3.55 on the 3.07

Can the front end just be re geared to 3.07? Found a new gear set for abt 100

Don’t care if it loose a little speed just need a working 4wd for snow
 
Can the front end just be re geared to 3.07? Found a new gear set for abt 100

Don’t care if it loose a little speed just need a working 4wd for snow

I don't think it can without a new carrier either way. The carrier is different and you can't just swap gear sets either way. You need to find a 373 rear or a 307 front end. If you put it in 4wd now it will destroy your transfer case.
 
Can the front end just be re geared to 3.07? Found a new gear set for abt 100

Don’t care if it loose a little speed just need a working 4wd for snow

I see your 17 and I was long ago. but understand this isn't a just remove one and bolt on the new one deal ! there's a lot involved in changing out a ring and pinion set. and seeing how you didn't know not to mismatch a 3.07 and 3.73 I am doubtful you currently have the knowledge to do it. like I said I know I was 17 too. and thought things would be simple, like putting a 302 in a 71 Bronco with a 6 cyl. after many days of cussin and fightin I gave up this was in the early 80's before the internet !
 
So far the 3.07 has treated me decent on 31s besides the speedometer is all kinds of wonky it’s off by 5mh till you hit “70” then I’m somehow going 87😂

But i planned on replacing the spider gears in my Dana 44 slapping that back in there and keeping the 35 as a spare
 
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