trans swap

[chevy283]

a have a 1965 c10 283' a it has a stock manuel 3 speed i was wondering if a th350 auto would give me better mpg i have a 3.73 rear in it

[60-66 Nut]

Not likely, since the high gear in the 350 is 1:1 just like the 3spd, plus the convertor slippage could make it worse. You'd probably have to go to an overdrive to really help. A 700R4 would be just as easy to install as the TH350, you just need to run a hot wire for the lockup. Hope that helps.

60-66 Nut

[chevy283]

700r4 would give better mpg would a t5

[chevy283]

there is a 1988 od 700re for sale for $250 is that a good price

[60-66 Nut]

A T5 would do OK also, but I think the 700 would be an easier install. Maybe someone who has done the T5 swap could tell you for sure. If that 700 is in good condition, that's a very good price, at least around here anyway. The 83-84 700's are not supposed to be quite as tough as the later ones, or so I have read.

60-66 Nut

[zenish]

the manual will give better mileage.you should change your rear gear,get a t5,get a three speed with overdrive if you can find one,or change to an overdrive automatic.

[Ed Cardinal]

The 3.73 rear was the most comon in these trucks but I do not think you can just switch out the gears in that rear unless you plan on going the other way and making them steeper like a 4.11 rear or something. Otherwise I believe the pumpkin will not fit the milder gears in it. You would have to get another rear to do it. And then you would probably want to go around a 3.36 or 3.08 otherwise you will sacrifice too much power / torque.
Remember the 283 is a very high reving motor and will tolerate the steeper gears much better. Also if you are running a stock 2-barrel carb you will want to change it out for a small 4 barrel with vacuum secondaries. If you pick the right carb and set it up right it will give you better mpg and more power when you need it. Just don't STOMP on it all the time or it will defeat the purpose. And a 3.73 is actually a good configuration for that truck. I would probably just drop in a 700R4 trans if you want it to purrrr on the HWY in overdrive and give you better mpg. That would be the easiest swap..........Ed.

[chevy283]

so i should replace the cab with a 4 barrel and trans with a 700r4 and i should get 17mgp?

[zenish]

a quadrajet four barrel will get better mileage than an aftermarket carb.

[Ed Cardinal]

I would probably swap out the carb first and see how that works. The quadrajet is a great carb and would work nicely if you get the smaller CFM one. Edelbrock makes new versions of them for a decent price. If they are set-up right and not over jetted they are truly the best for these trucks.
And if you can't find a stock manifold you can go with an Edlebrock performer (not the RPM model). Even if you have to paint it to make it look more stock. Then after all that see how it goes. Unless you are doing a lot of long trips that set-up should be fine. And if you decide to sell the old auto trans let me know..........Ed.

[chevy283]

i don't have a auto its a manuel 3 on the tree

[qksilver]

a 200 overdrive would mean not having to cut the drive shaft and the trans yoke might even be the same. Plus they have better gearing for a smaller motor and don't use as much power either. You would still have to reposition the crossmember, add TV linkage and shift linkage

[chevy283]

200r4? im new

[chevy283]

is the 200 overdrive from a chevy?

[zenish]

some 200r4s only fit buicks,olds, and pontiacs.some are also drilled for chevs.

[Blue Beard]

Does the Trans mount have to be changed as well?

[chevy283]

so it would be easer to just go with the 700r4