Engine and transmission swap on 77 C10

[goodmand]

Hey folks. Pretty new here but...

I'm looking to turn my 77 1/2 ton C10 into a daily driver/airstream towing machine. I've read some of the posts on here but wanted direct input from anyone listening...

I want to be able to pull at least 7000-8000lbs with the thing. By replacing the motor and trans with something beefier (not to forget the brakes too), am I actually barking up the wrong tree? Currently the truck has a rebuilt 350 that has its own issues and might not be worth saving.

Thanks in advance

D

[Irish_Alley]

my 91 v3500 has a 350 4l80e/205 srw is rated for 9200 lbs. now a 3500 is going to have a thicker and taller frame than a ½ton not to mention axles which can handle the weight. dont think you can do anything to your frame to have it "rated" for that much except maybe axle/spring swap with a 1 ton and boxing in the frame.

imo if you were in love with your 77 or it was a nice body i would look for a 1 ton to do a frame swap.. but mind you even after the swap and d.o.t. sees you youre still only technically only at 1/2 ton gvwr,  unless you get your truck recertified.

what are you hauling?

[goodmand]

Alrighty I get it. Thanks for that. I am in love with my 77 and should probably just get it through my thick skull that it's just super light duty. I want to tow an airstream and keep up with the vintage look of that with a vintage truck towing it... Most airstreams come out to around 5000lbs but Im a chick so we all know there will be a ton of other stuff in there on top of the base weight   

[goodmand]

Now I wonder would a 67-72 c20 or c30's frame suffice? I'd still put in a brand new 350

[Irish_Alley]

im not sure, i think you can make it work but you have to move mounts around. for a camper D.O.T. shouldnt bother you i know around here theyre pretty much going after business they dont care about recreational use. as long as your truck brakes work and your camper has good brakes thats all you need but i would want to move up at least a ¾ ton. a ½ ton the gvwr is going to be between 4300 and 6200 the different ratings came from more springs (4, 5, 6 and , better tires and brakes.

a ¾ ton is going to be between 6400 and 8200. aside from having a little bit of a thicker frame 3/64" and a heaver axle/s is again springs(5, 6, 7, 8 and 9), better tires and brakes.

[Jason S]

There are several postings here from Sgt. Del (or Lt. Del) about his '79 C-10 you may want to look for.

http://forum.73-87chevytrucks.com/smforum/index.php?topic=2962.msg12984#msg12984
http://forum.73-87chevytrucks.com/smforum/index.php?topic=4939.msg23050#msg23050
http://forum.73-87chevytrucks.com/smforum/index.php?topic=3528.msg15995#msg15995

He uses his C-10 with a 383 for pulling a camper trailer.

He also has a web page where he discusses what he did, http://www.delbridge.net/.  On the left side of the screen click on "My 1979 Chevy Pick up."  On the webpage he says "I adapted this old Detroit metal... into an 8,000 lb towing machine."

[rich weyand]

Squarebody half-ton Cs have a towing capacity of 8000 pounds for a braked trailer, like your Airstream.  Not a problem.  That's assuming a 350 or bigger engine, auto trans, power brakes, and the correct hitch and brake controller, and assuming any spring/shock replacements along the way met stock specs.

The tongue weight on a trailer should be about 10% of the gross weight, which means you are looking at 700-800 pounds on the hitch.  You should not load the bed of the truck with enough stuff to exceed the GVW when you add in the truck weight, passenger weight, tongue weight of the trailer, and cargo weight.  The GVW of each axle of the truck should be listed on the badge in the driver's door opening.  Your truck weight should be just shy of 4000 pounds.

That said, you want an equalizing hitch for a trailer like that.  This type of hitch will apply a torque to the hitch that transfers some of the tongue weight to the front axle.  It will keep you from overloading the rear axle springs, dragging tail in the truck and having the front end be light -- all of which are bad.  It's also nice to have a sway control hitch that keeps the trailer in line, especially if it is a single-axle trailer.

Finally, you need a proportional brake controller to control the trailer brakes.

Here is an example of an equalizing hitch:
http://www.etrailer.com/Weight-Distribution/Pro-Series/PS49902.html?feed=npn&gclid=CNPFuL_1h8MCFc1_MgodtyAApw

Here is an example of an equalizing hitch with sway control:
http://www.etrailer.com/Weight-Distribution/Reese/RP66088.html?feed=npn&gclid=CIj_hu31h8MCFSwLMgodnwwASQ

Here is an example of a proportional brake controller:
http://www.amazon.com/Reese-Towpower-78077-Echelon-Proportional/dp/B0049MX7C8

Any decent RV joint can set you up.  They will know who to see locally to get the proper hitch welded onto your truck.  You do not tow a trailer like that with a bumper hitch!  And you want a very capable guy doing the welding.  Ask around.  Find a local camping club, like a National Campers and Hikers Association affiliated club, or ask on an RV forum, to find out who in your area knows what they are doing.  Some serious research here will forestall a lot of problems.

As for brands, when I was towing trailers, Reese made good stuff.  I suspect they still do.  Again, ask around with the RV people.

As for the trans, a TH350 trans will take a lot of abuse.  Depending on how many miles are on yours, you might want to get a new one.  Towing a trailer builds a lot of heat in the trans, which is destructive to the trans, so for towing it is probably best to run synthetic ATF (which heats up less), and install a separate trans cooler.

As for the engine, the base GM crate engine (350/260hp, GM #10067353) is a good engine with a lot of torque for cheap.  Under $1600 from JEGS, delivered.  You can have a 12-300-4 cam installed in it before the engine goes in, which will make it an absolute beast for towing.  Probably want to move the shiftpoints down 500 rpm with that cam, by changing out one weight in the TH350 governor for the next heavier weight.  Say that to your mechanic and he will know exactly what to do.  Or you can stick with the base crate engine and keep the warranty in place.

I don't think there's a problem, IF YOU GET THE RIGHT EQUIPMENT, along the lines above.

[Captkaos]

Now I wonder would a 67-72 c20 or c30's frame suffice? I'd still put in a brand new 350

can add anything to rich's post but 67-72 frames are shorter by 2.5" in wheelbase.

[Irish_Alley]

weve used blazers to haul  loaded trucks before. 350 sm465 (manual trans) with no problems. also back in the 70s gm still used 6 cylinders in their 1 tons.

[Jason S]

also back in the 70s gm still used 6 cylinders in their 1 tons.

I've seen an 80's former Canadian Railroad crew cab, K-30 with a 292 and SM465.