granny trany help!

[jrick63]

Im 20 learning how to restore my first truck. I need a few question answered.
I have a 1965 c20 4sp. Well i decided after some thinking that I'm going to drop a 350 in. I would like to keep it a manual. What's the best/easier route to go. Being that its a 3/4t there's a little weight to push around.
Can i keep the transmission and change gears/rear end?
Or change transmission and keep rear end.?

I appreciate all answers!
Thanks, jrick

[jtrichard]

whats in her now? why do you think you need to change rear gears?

[jrick63]

Motor is a 283, not currently in. And needs to be rebuilt. I just heard that the trucks were geared low. I would like to be able to cruise.

[jtrichard]

they are low geared i have a 63 had since 67 it will do 70+ but it has 750/17s.... not a lot of gears available for these you may want to change the rear axle to later 14 bolt much easier to get parts for.... i am putting a 81 cab and chassis in mine they are the same width....... the standard 3/4 ton 73/81+ are 1-1/2" wider 3/4 each side as for the engine change it will bolt right in

[jtrichard]

you need to find out just what gear ratio you have and WE need pics .... ps welcome to the world of 60s chevy pickups

[jrick63]

If i change to a 14bolt will that still be 8 lugs?

[jtrichard]

yes 8 lug ... looks like the best you can do gear wise with yours is 4.11.... 14 bolt with 3.73s are very common

[jtrichard]

and later you can get 73/81+ front disc brakes also then you have better braking and easier parts

[jrick63]

So 14 bolt with 3.73 would be best? Can i keep the Trans then?
Sorry for all the questions! Gotta learn some how

[jtrichard]

yes you keep your trans there is some work to do any of these mods you can search here for posts on how each one is done

[jtrichard]

here is one on the 14 bolt there more http://67-72chevytrucks.com/vboard/s...=483346&page=2

[jrick63]

And what years will match up. Right now there is a guy with 14 bolt 273 from 97 3/4t (not a full floater)

[jtrichard]

late 80s i think...... personally i would not use the non floater even if it fit

[Captainfab]

I typically discourage using the '88 and up pickup differentials as they are a lot wider than the early differentials, but the Eaton HO52 that is likely under your truck now should be 65.5" wide WMS to WMS. That '97, 9.5" 14 bolt should be 64.75" wide, which would work under your truck. However I would suggest verifying those measurements on the actual differential you are looking at. Also be aware that the 9.5" 14 bolt was also available in a 6 lug version, which is often found under the light duty C2500's and some K1500's.

Originally Posted by jrick63

And what years will match up. Right now there is a guy with 14 bolt 273 from 97 3/4t (not a full floater)

[jrick63]

Here is the ad i seen...It is out of 1997 3/4 ton HD 4x4, 8 lug (NOT a full floater) with only 170,000 miles on it. Tested and works good

[jrick63]

[jtrichard]

nice ... looks like you need rear cab mounts .. get a set out of a 1/2 ton frame brackets and all

[jrick63]

[jrick63]

[jtrichard]

find a 73/88 3/4 ton that has no engine and a rusted body for parts donner and you will have rear axle, front cross member/disc brakes, power brake and power steering ......looks like you have been busy on it already

[jrick63]

Will i need to change out the front cross member ?

[Captainfab]

As far as I know, yes you will have to change the entire suspension, including the crossmember, on the '63-'66 C20's Another member claims otherwise, but it has not been verified yet.

Originally Posted by jrick63

Will i need to change out the front cross member ?

If you want to change those sagging rear cab mounts, I have a C10 set here:

http://www.67-72chevytrucks.com/vboa...d.php?t=604784

[jrick63]

Whats the reasoning for having to change it out?

[jtrichard]

there different ways to get the disc brakes on the front change the whole thing ( i am doing that as i have a 82 with a good front suspension and grease-able control arms i hate rubber) you can change the arms and spindles or you can change just the spindles and ball joints

[jrick63]

Ohh you guys are talking about if i switched everything to disc