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Old 08-28-2017, 12:48 AM   #1
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Question Reviving my 72- NEED ADVICE

I appreciate all you guys so much for all the helpful advice that I figured I would reach out to yall for help. Current situation- Im graduating grad school in Dec and I plan to be able to get my 72 c10 running when additional funds are available. I originally had a turbo 350 transmission but the prior owner had placed a lower geared rear end in the truck. So, as you can expect I couldn't hear my father talking at 50 mph and him sitting next to me riding.
I arranged a transmission swap out for a 700r. Long story short it apparently wasn't installed correctly and burned up. Now I sit with a motor outside the truck, while getting the fire wall repainted, repainting the motor/new valve covers ect.

Im tempted to go with an LS swap but have no clue how much money I would be running into, motor/transmission/wiring harness installed and all. And would I need a lower geared rear end with a LS swap? Any and all advice would be great.
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Old 08-28-2017, 11:15 AM   #2
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Re: Reviving my 72- NEED ADVICE what I am hearing is that you are on a bit of budget with all of this...ok, thats a good start point.
So you have 2 main problems....1) one is that the existing diff in your truck is geared to low to be useful ....and 2) you currently don't have a transmission for your truck.
If you going to do an LS swap get ready for putting out money well into 4 figures (thousands) to get it you have the budget and time for this?
If not...then consider finding another TH350 transmission or maybe another 700R series if the driveshaft, etc has already been modified for the 700 trans....there are lots out there and you might be able to find a quality used one without too much trouble.
Then I would look to find a correct '72 stock differential with the 3.07:1 ratio. I you go to any local wrecking yard they might have a truck in there and you could get that diff for a few hundred bucks.
If you needed to regain some money, then you could resell the low geared one you have in there.
There are enough of these trucks out there as parts trucks, wrecking yards etc that finding a diff shouldn't be too difficult if you do some searching and they aren't all that tough to put in.
my two bits.

....for some men, there is experience, skill and effort....for the others...there is visa and UPS LOL
1966 Chevy 1/2 ton (Florida- Red/white)
1972 Chevy 1/2 ton (California- Blue/white)
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Old 08-28-2017, 11:46 AM   #3
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Re: Reviving my 72- NEED ADVICE

Was it as simple as the TV cable wasn't adjusted properly? That'll burn them up fast.

Sounds to me like if you already have a motor and transmission, get the trans fixed up and put it back in (and this time adjust the TV if that was the problem). An LS swap will run you a fair bit of money that you don't anticipate up front.
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Old 08-28-2017, 12:43 PM   #4
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Re: Reviving my 72- NEED ADVICE

do you know what gear ratio you currently have?
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Old 08-28-2017, 12:46 PM   #5
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Re: Reviving my 72- NEED ADVICE

I would say a budget LS swap with a used motor and trans, doing all the work yourself, would be around $2500.

Keep in mind this is buying a used engine/trans, so who knows with aprox 100k worth of miles... what type of problems you'll get into.
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Old 08-28-2017, 02:28 PM   #6
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Re: Reviving my 72- NEED ADVICE

Personally, I wouldn't recommend a 3.07 with a 700R4. Just too high of a gear in my opinion, unless you want to cruise in the mid-80's on the highway. 3.73 was standard for most 1/2 tons that came with 700R4s in later years and that is a very streetable combo. Would be good to know what you currently have and then we can help you from there. Would also like to know your planned tire diameter.
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1972 c/10, ls swap, motor, rear end, transmission

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