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May 30, 2003 | 10:02 PM

venom69

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gear questions

ok i have a 77 ford f250 with dana 44 up front, dana 60 in back. guy i bought it from said it had 4.10 gears front and back and posi front and back. well broke the front gears and having to replace them. turns out the front is not posi. also turns out that i have 5.25 gears. well i found a place that had a posi unit for my dana 44 and 4.10 gears on it all ready. my question is should i stay with the 5.25's or should i go with the 4.10's and switch out the rear 5.25's with 4.10's. i dont do a whole lot of 4 wheeling or climbing but i do go out and play in mud and i do some hill climbing. it would be a street truck most of the time though. thanx in advance

May 30, 2003 | 11:42 PM

heep70

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Joined: Jan 2003

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From: Bonney Lake,WA USA

gear questions

4:10 if you want to run on the highway also. I have never heard of 5:25 gears, maybe they are 5:13?????? Anyway I run 4:10, they are a bit tough on the wallet as far as gas, but they allow me to climb around in the woods and run on the highway.

May 31, 2003 | 02:43 AM

MustangGT221

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From: Topsfield, MA

gear questions

How big of tires? What RPMs do you run currently at 65 mph?

May 31, 2003 | 08:56 AM

venom69

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gear questions

well i do some highway driving and right now i am running 36 in tires, but will be down sizing to 33's. as far as gear ratio i thought it would be hard to find this type. it is stamped on the ring gear as 43-8 and says dana on it, when you do the math on it it comes out to 5.25. just has me wondering if i could even find the ratio, might have better luck just replacing the rear with 4.10's

May 31, 2003 | 09:31 AM

MustangGT221

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From: Topsfield, MA

gear questions

If you're going to be using the 33's for the driving than 4.10 wouldn't be a bad choice. Do you have overdrive? Do you do a lot of highway driving?

May 31, 2003 | 09:43 AM

StrangeRanger

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From: Copley, OH

gear questions

43:8 is a 5.375:1 ratio, 42:8 would be 5.25:1. Either way that's a lot of gear. With 35s that's about equivalent to about a 4.30:1 with the stock 29" tires. If you swap to 33s, then the 4.10s will work out about right (about equivalent to 3.55s with stock tires) for geneal use but may be a little too tall for the mud and the blood and the beer.

If you were starting from scratch with the 33s, you'd probably be better off with something in the 4.30-4.56 range, but since you have the access to a cheap 4.10.... It's your call.

EDIT:
I just noticed it's a 77. That means no OD tranny, right? It also means you've probably got an NP435 or a T-18/T-19 with a granny 1st. The 4.10s should be fine with that much reduction available.

Last edited by StrangeRanger; May 31, 2003 at 09:47 AM.

May 31, 2003 | 10:11 PM

venom69

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gear questions

just an update. i decided to go with the 4.10's and have completed the front today, i will tackle the rear tommorrow. i will post an update of how things go and how it does in 4 wheel. everyone here has been great and very helpful, not sure if i could have done it without your guys help. much thanx to everyone. also i noticed about the tranny. i would like to find out what i have, i thought i had the np205, how can i tell which one i have?