Is this the right forum for dif questions? Reaend gear ID

[chevjerico]

Guys' how can I find out what gears my truck came with stock?

How much would it help my MPG going from 4.10 to 3.54? I don't even use 1st gear at all. Stock Getrag gear box.

[BILTIT]

I dont use 1st gear with 3.54's and 33" tires either unless i am pulling fairly heavy.

What rpm at what speed with what size tires? We should be able to tell you just from that.

[chevjerico]

Thanks but it has 4.10 gears. Just wondered what it came with. I have the original window sticker, and I'm sure there is an axle code stamped on axle. Maybe other ways?

[BILTIT]

Take your VIN to the dealer, they can tell you what it had originally.

Why do you not think the 4.10's are original?

[chevjerico]

The previous owner told me the gears had been replaced at some point when the truck was relatively new. Said he had to change out speedo gears to correct error.

How much MPG do you think I can get switching to 3.54 gears? I'm getting 17.8 MPG around town now, and actually I'm pretty happy with that. If I come across a good deal on a rearend or gear swap, I might give it a shot.

I can't imagine this truck needing any more then 3.54 to pull a load. Especially the loads I'd put on it. An open car hauler, and 4k lbs car. I guess around 6k lbs, or a small toy hauler probably of similar weight.

[chevjerico]

Take your VIN to the dealer, they can tell you what it had originally.

Why do you not think the 4.10's are original?

Oh hey Biltit, I love Venturas! I have a 70 Chevelle 4 speed, best ET is 11.85 on an econo built 400 with stock vortecs and different springs. I'm more a Buick, Olds, Pontiac guy, then Chevrolet.

[BILTIT]

sweet, 11.85 is nice!

Rolled my first one.

Second one served me well for many years but is undergoing a minitub and diff narrow right now.

[chevjerico]

Nice.....TA girdle and cheater slicks! Actually my best last time out was 11.97 @ 112 also!

[BILTIT]

Haha thats funny.

Ya i needed the wide tires to hook on the street, we do alittle street racing around here

[PToombs]

Love the rubber up on the quarters, that brings back some memories.