V8 Swap Gearing (1 Viewer)

[Josey1972]

I bought a well used 1976 with a 350 and 700r4 tranny. It has a split Tcase. It’s running stock 4.10 gears.

I’m getting ready to rebuild the well worn thirds. I need to decide if I should change to a different gear.

The truck is on 37’s. My hope for the truck is to be able to drive it anywhere, wheel it and drive home. I’m in the Midwest so the old girl will see a good bit of pavement.
I’m looking for opinions on gearing.

I think 4.88 would be a likely option but hopefully those who know the set up can weigh in.

appreciate suggestions.

 

[matzell]

4:88's should make that happy. The v-8 should spin up to 3000 all day long without issue. You should be well below that with the overdrive.

 

[B y r o n]

So what is your opinion of how it is acting with the 4:11 gears?

Do you need more low end or more high end?

Are you wanting more low speed torque or lower RPM cruising?

 

[Josey1972]

So what is your opinion of how it is acting with the 4:11 gears?

Do you need more low end or more high end?

Are you wanting more low speed torque or lower RPM cruising?

I’m fairly happy with it on the highway but it’s the only 40 I’ve ever driven. I have yet to wheel it as it needs some attention before I do that. I’d like to get a little more fuel efficiency out of it. I have no grand expectations. My realm has been the 80’s. I’m on 35’s and 5.29’s on it.

 

[74fj40]

Since you have an overdrive transmission, I would absolutely do 4.88s.

you’ll really appreciate the low end power gains.

 

[pb4ugo]

Going to 4.88's is not going to increase fuel mileage, but they will be great on the trail..

 

[BrianSanDiego]

What RPM is it spinning at cruise speed?

 

[Josey1972]

What RPM is it spinning at cruise speed?

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