I have to ask this question since I have always thought the difference between chevy and GMC has been in slight differences in options and minor sheet metal differences. Now that I have acquired my first GMC and I plan to invest considerable amount of time (and perhaps money, hopefully not too much!) I thought to get this out of my way. I have a 1953 GMG 3/4 ton. What is the differences between Chevy and GMC 1/2 tons and 3/4 tons? Of course besides being 1/2 and 3/4 tons and different suspension set ups in relation to their gross wt. I just learned that chevys are considered AD and GMCs are new design (ND?)? Also I learned that GMC is positive electrical versus chevys are negative ( So how can I jump start a GMC, connect the leads backward?!) Does online brake kits, suspension parts, cab patch panels, and etc will be interchangeable between chevy and GMC? Please let me know about any differences that you know then I would save some time and money on my upcoming 1953 GMC 3/4 ton project. I plan to keep the truck 3/4 ton. I am sorry of this is a very basic question. Thanks
1953 GMC 150: new member 1967 Chevy C20, 4 wheel 8 lug disc, 350 engine with Fitech carb (in progress) , T5 1972 Chevy Nova, 4 door sport sedan in the making 1979 Chevy Camaro Z28, 5,3 Vortec and TH350, 4 wheel disc and Hydroboost; Just about becoming summer daily driver
Howdy, All of the suspension parts, patch panels (with exception of dash panel), brakes etc will interchange between the chevy and GMC versions. Your drivelines will be different of course, different engines, the trannys i believe will interchange though. Are you planning on keeping it stock? What are your plans for the truck?
Yes and no to the question if I am going to keep it stock. I like to keep it 3/4 ton, specially keep the 8 lug wheel set up but also I want to use as much as modern drive line as possible to have a nice smooth reliable truck. I like to keep it stock height. I have a 5.3 vortec and a 5 speed manual transmission, I am thinking to use a chey 14 bolt rear to keep my 8 lug. The front is different story. I have seen a 8 lug disc conversion for 55 chey and newer which may fit my application with some tweaking but I am not sure how the solid front axle rebuild cost and since I am planning to go V* engine, I may have to relocate my steering box or go rack and pinion section. This is what I know now.
1953 GMC 150: new member 1967 Chevy C20, 4 wheel 8 lug disc, 350 engine with Fitech carb (in progress) , T5 1972 Chevy Nova, 4 door sport sedan in the making 1979 Chevy Camaro Z28, 5,3 Vortec and TH350, 4 wheel disc and Hydroboost; Just about becoming summer daily driver
The only difference in the front fenders is the presence of a hole for the parking light. I have a GMC front fender on each of my '49 and '52 trucks. I just welded the holes shut. One could drill a hole in a Chevrolet fender for their GMC parking light. You won't need to move the steering box if you use exhaust manifolds from a '55 265 cubic inch V8. They are very narrow and dump downward toward the front of the engine. You definitely don't want a rack and pinion for a straight axle. Too much going on to make it safe to drive.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
What motor is in it now? 228 248 270 ? Do you know?
I Think the engine is a chevy 235. This is the engine code : F0306J Carl, I plan to use a LS based vortec engine, so I am not sure if I can use the 265 V8 manifolds. Can I? I guess custom header can be a possibility but the $$ is limited.
1953 GMC 150: new member 1967 Chevy C20, 4 wheel 8 lug disc, 350 engine with Fitech carb (in progress) , T5 1972 Chevy Nova, 4 door sport sedan in the making 1979 Chevy Camaro Z28, 5,3 Vortec and TH350, 4 wheel disc and Hydroboost; Just about becoming summer daily driver
When jump starting, ALWAYS connect positive to positive and negative to negative, no matter which is grounded. Hopefully once you get it going you won't need to jump start it.
In '53 3/4 tons, the two are pretty much identical from the motor back. Sheet metal's already been mentioned. GMC is 6V positive ground and Chevy negative ground. The longer full pressure oiling of the GMC inline six the biggest difference overall. The oil press gauge in the GMC will go to 60 psi; the ammeter reads -50 | 50+ where Chevy is C or D, but speedo and temp gauge are identical. You have lots of options on the 3/4 ton rims depending on what you want to do with it for look. On my '51 3/4 ton, I had the original rims centers cut and new outer rims welded on that moved me from 15" two piece rims to 16" tubeless rims but I kept the original hubcaps. I upgraded that to a 302 GMC inline and A833 OD and it's very comfortable on the road at 65-75. Added a front sway bar and radial tires along with Juliano's 3 point seat belts Still 6V + ground and it runs great. Have driven it from Boston to San Francisco and back so it's a highway runner.
In '53 3/4 tons, the two are pretty much identical from the motor back. Sheet metal's already been mentioned. GMC is 6V positive ground and Chevy negative ground. The longer full pressure oiling of the GMC inline six the biggest difference overall. The oil press gauge in the GMC will go to 60 psi; the ammeter reads -50 | 50+ where Chevy is C or D, but speedo and temp gauge are identical. You have lots of options on the 3/4 ton rims depending on what you want to do with it for look. On my '51 3/4 ton, I had the original rims centers cut and new outer rims welded on that moved me from 15" two piece rims to 16" tubeless rims but I kept the original hubcaps. I upgraded that to a 302 GMC inline and A833 OD and it's very comfortable on the road at 65-75. Added a front sway bar and radial tires along with Juliano's 3 point seat belts Still 6V + ground and it runs great. Have driven it from Boston to San Francisco and back so it's a highway runner.
That sounds great. Couple of questions: Where did the work on your rims? Can any truck tire shop do that? Second, is the front straight axle different (bigger or smaller) between the chevy versus GMC and between 1/2 ton versus 3/4 ton? Thank you everybody for educating me on this trucks. Cheers
1953 GMC 150: new member 1967 Chevy C20, 4 wheel 8 lug disc, 350 engine with Fitech carb (in progress) , T5 1972 Chevy Nova, 4 door sport sedan in the making 1979 Chevy Camaro Z28, 5,3 Vortec and TH350, 4 wheel disc and Hydroboost; Just about becoming summer daily driver
Carl, you sure they're GMC fenders? They look different in this pic... of twin 49's.
Course I haven't disassembled either clip, just removed both clips in their entirety. Would be very handy if they are interchangeable....
Dave
Absolutely positive they are identical except for the parking light hole. What is throwing you off is the GMC upper grill surround covers up a significant potion of the fender making it look quite different.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
That sounds great. Couple of questions: Where did the work on your rims? Can any truck tire shop do that? Second, is the front straight axle different (bigger or smaller) between the chevy versus GMC and between 1/2 ton versus 3/4 ton? Thank you everybody for educating me on this trucks. Cheers
I got my rims changed in 2006 and they were done by Stockton Wheel in Stockton California. At the time, they were the only ones doing that type of work but now there are many that can do that. Ask around. Front axle on 1/2 ton and 3/4 ton are different and not interchangeable; six lugs on 1/2 ton and 8 on 3/4 ton but Chevy to GMC front axles in same size truck are the same.
1/2 and 3/4 ton axles are all different parts, but they are swappable as a whole assembly because same spring size and spacing. If for whatever reason you wanted the 1/2 ton front axle in a 3/4 ton truck or the reverse.
Well Carl, absolutely is good enough for me, LOL. I've currently got the front clip off the 3100 and went out and did some measurements yesterday and was surprised how close they came out. OP, disregard my statement on the fenders, I was wron,,, err ahh mistaken. (which ain't the 1st time)....
We have a '53 GMC half ton. It's a Canadian made version apparently so it's called a 9300. The '53s came with a full pressure Chevrolet 235 that the american trucks got in '54. Just about everything is interchangeable with the exception of the ring gear carrier, it's slightly different for the Canadian trucks for some reason.
Edit: I noticed even the wheel (ball) bearings were made in Canada. When I repacked them last spring I had to replace one as one ball out of them all had some scoring. I guess 65 years is a good run for a bearing.
Ball bearings in the wheel bearings on these trucks may well be the most durable moving part on these trucks. Grease them, torque them to 33 ft lbs, back them up a hair past 1/12th of a turn, but not more than 1/6th of a turn, and run them forever or so. Carl
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
Ball bearings in the wheel bearings on these trucks may well be the most durable moving part on these trucks. Grease them, torque them to 33 ft lbs, back them up a hair past 1/12th of a turn, but not more than 1/6th of a turn, and run them forever or so. Carl
I was going through pictures on my phone looking for something else today and found a pic of the bearing.
