View Full Version : 1/2 ton strength vs. 3/4 ton

04-14-2001, 04:02 PM
About how well does the 1/2 compete against the 3/4 as far as off-roading goes? I know the 3/4 ton has heavier axles but does this really help when going off-road with say 33 size tires? I figure this is about the max size Super Swamper tire I should get for my 1/2 ton. The suspension can be made all the same can't it? How much can the 12-bolt take off-roading? Is it durable enough?


karl klein
04-14-2001, 10:05 PM
i feel a half ton truck is better becuase the stronger springs on a 3/4 ton dont give you as much control

04-15-2001, 12:14 AM
I think a lot depends on how aggressively you plan on driving your truck. IMO, the most important factor is the driveline - especially the axles.

If your going to be "pounding" on it, I'd advise going with the heavier-duty (3/4 ton & up) trucks over a 1/2 ton. If on the other hand you just plan on the occasional rough-country excursion, the 1/2 ton should do OK as long as you drive it sensibly - the 1/2 ton driveline parts ARE lighter (= weaker). And, the newer the truck the lighter everything is.

Up until '80, GM used a (strong) full-floater axle in the rear of their 3/4 ton trucks. 1-tons had full floating axles front & rear and kingpins instead of balljoints on the steer axle. http://www.chuckschevytruckpages is a good place to find out more about the parts combos.

About 10 years ago I helped a friend of mine build a "Godzilla" truck based on '79 Chevy 3/4 ton running gear. He lived about half a mile from some vacant land we called the "dunes" which was our R&D lab: Build something, take it out there & pound on it, and if it broke it wasn't adequately designed/built! While not everything we built worked out 100%, we always made it home under our own power!

We're both currently building one truck each: Both will be 1-ton 4x4's, with everything built heavy-duty to match. We like 'em strong! Disadvantage? They're heavy - and they like their fuel! Since neither will be a daily driver, mileage wasn't a huge concern.

John DiMartino
04-15-2001, 01:04 AM
the 1/2tons do better due to better articulation,and lighter weight.The soft suspension,and smaller differential pumpkins,give it better traction,and increased ground clearance.The problems start if you overload the truck/and or put big tires on it.If you leave it stock-or even go 1-2" bigger tires,you're OK for mild wheeling-but if your going to hammer it-say good bye to U-joints,rear ends,trannyETC--.So if your goin to lift,and get big tires,carry lots of weight off road-get a 3/4 ton HD-with full floating rear,8 lugs.

04-15-2001, 06:39 PM
I plan on putting 33x12.50-50 super swampers on it. As far as off-roading, it is mostly going to be a hunting truck. The roads around my place are really muddy and poorly maintained so I imagine I'll get into stuff like that. it is not going to be a recreational off-raoding pick-up though. Well, maybe once in a while. I dont plan on stump jumping it though.

04-16-2001, 03:32 PM
I don't know what kind of soils (clay, silt, sand) you are talking about when you say you will be mudding up and down poorly maintained roads but I have this picture of a road like those around here which the primary problems is keeping it in the road and keeping it moving. We feed lots of cattle down roads that a lot of "off roaders" in our area claim to be impassible with their machines (because they spin on top of the clay and silt). Our secret is very tall (for axle clearance) and narrow (to sink through the slop and get to solid ground) Farmland tires. This is on very heavy vehicles such as One and three quarter ton trucks with single wheels and Dew-eze hydrabeads (weighing close to a ton by themselves). On top of that we will have at least a ton and a half load on the bead. When you try to make it through the feilds, you have to be carefull where you let the load off, because when you are unloaded, you likely can't make it without a fast run at the slick spots. Otherwise, we just crawl around in granny gear through just about anything.

This of course will not work if the road has no solid subsoil like some of our quicksand hills where you sink to your axles. In this situation, you are better off with the lighter vehicle with mile wide swampers.

Just some things to think about.

04-16-2001, 04:17 PM
Well, around here we have city people come over in their gigantic off-roaders and they tear the hell out of everything. Deep mud with solid ground beneath is about how it is. Lots of pot holes and whatnot. Lots of snow during this time of the year too. My idea of off-roading is crawling through muddy terrain, not flying through it(unless the roads are in good shape) so I need the best traction available. Flying through a mud hole and then slamming a foot deep or more pothole is not good.

04-16-2001, 04:19 PM
I live in the Pacific Northwest. Wet wet wet.

04-16-2001, 11:03 PM
I would go with the 3/4 ton, cause there is a big difference between the two as far as carrying stuff. The 3/4 ton can carry MUCH more than the 1/2 ton. They are heavier duty and can take more abuse. Also, a stock 3/4 ton is higher than a stock 1/2 ton is, so theres your ground clearance.

04-16-2001, 11:09 PM
I don't plan on carrying much of anything in this truck. It is strictly going to be a recreational vehicle. Whenever I do carry anything its not going to be coupled with hard driving conditions. Besides getting a 3/4 ton rear axle is there anything else I can do to beaf up my truck to prolong component life?


04-16-2001, 11:17 PM
I am just speaking about overall strength. The 3/4 ton is much more durable than a 1/2 ton is. If you want more strength, go with either a TH 400 tranny, or the 4 speed, and go with the 205 Transfer case. Thats the real deal there.

04-16-2001, 11:20 PM
Good point Rich - only problem I can see is (based on what we found out on that "Godzilla" truck we played around with), then the weak link (there ALWAYS seems to be one of those! :( ) becomes either one of the driveshafts or the 1/2 ton axles themselves. Once you start building up one part of the truck you pretty much need to build up everything. (That's why I'm using K-35 components!)

Garet, based on what you've stated about the intended uses for your truck, and what the others have posted, I'd say leave it the way it is & you should be fine.

BTW, what year is your truck? '73 - '80 were pretty strong even in the 1/2-ton range. '81 and up GM started saving weight wherever they could, so the 1/2-tons from that era aren't as strong (in my opinion) as the earlier ones.

If you go to swap axles, you'll want to do both since the gear ratio must be the same at each end of the truck. Same with tires, they've got to be the same all around and with the 3/4 ton rear axle, you'll end up with mismatched wheels (8 lug wheels on the back).

As I posted earlier, drive it sensibly & I think you'll be OK.

[Edited by 75 on 04-16-2001 at 10:26 PM]

04-16-2001, 11:31 PM

04-16-2001, 11:37 PM
Hey! That's older than mine! :D

You've got a pretty strong unit then, even if it "just" ;) a 1/2 ton! And - first year for that body style too!

04-16-2001, 11:48 PM
I was trying to figure out if my U-joints were shot yesterday with a friend. I had him look at the rear driveline where it meets the yoke to see if there was any play in it. He noticed that when I put it in gear it would clunk and the rear axle would jump up a bit. I'm not sure but do U-joints cause this to happen when they get loose. It seems like it would since power is not being distributed properly to the rear end.

mike reeh
04-17-2001, 01:32 AM
yep sounds like your u-joints could be bad. put the trans in neutral and see if you can wiggle it at all.. there will also invevitably be play in the rear end gears, and in the transfercase output shaft so dont let that fool you.

i agree with "75"... from what Ive read I think you're fine with a 1/2 ton.. the main problems that you will probably have with the half ton running gear, in your situation, is worn-out parts, rather than stuff breaking because it was built too weak..


04-17-2001, 09:03 PM
Thx for all the help guys.

04-20-2001, 02:34 PM
Put the truck in neutral and turned and shook the back driveline and their seems to be no play in u-joints but the driveline does turned a little before clanging to a stop. I guess this is normal, figuring the age of the axle. Hey, question.. Would an open axle be less damaging on components as a posi? It seems that there would be less torque overall being applied to the gearing. Of course maybe a posi unit keeps the torque in balance somewhat being that both tires spin rather than the torque being applied to just one side or another.


04-26-2001, 10:00 PM
I agree with everyone else. The 3/4 or 1 ton running gear is alot stronger. But, given your intended use and tire size, 1/2 ton should be fine. I run 35-12.50-15 tires on my half ton(Dana 44 front and corp 12 bolt rear) and have done some pretty radical offroading with little to no problems(from DEEP mud to some pretty hairy rock crawling).

04-29-2001, 06:17 PM
I think that the only thing that is really different about the Half and three quarter ton trucks is the rear axle. Sure, you can get several different Engine, Trans and Transfer case combinations but there is no comparing the 10 1/2" Full floating Rear to any other GM axle. I Love mine and after I added a Detroit locker I havent had any trouble at all. (I run 44" Mudders). The Front axle on Half and three quarter ton trucks are the SAME. Same size U-joint, same size axle shaft, same size spindle....and so on. Only the Dana 60 has larger components. I think that there were a very few 3/4 ton trucks labled as "Heavy Duty" from the factory that had an optional Dana 60 in the front. Anyway, you shold be ok with the Half ton equipment.....you'll know when you need to upgrade. It all depends on how hard you abuse your equipment, Rember....Drive it like you stole it!!!

04-29-2001, 10:51 PM
I heard that there is a way to add strength to a 12-bolt so it will not break. Apparently it does something to it which has the same characteristics as the 14-bolt. Anybody familar with this? A friend of a friend had it done by a mechanic after breaking his 12-bolt. I think something is welded. Anybody know anything about this?

04-30-2001, 09:07 PM
I dont know of any way to make the 12 Bolt as strong as the 14. The sheer size of the 10 1/2" Ring gear on the 14 bolt is a measure of its strength. It also has a pocket bearing that the Pinion shaft rides in making it almost imposible to deflect the pinion gear under heavy towing loads.

The 12 bolt is a C clip axle (this has already been covered so I wont expand) and the 14 is a full floater. Nuff said.

I have seen in a magazine a truck that took a 12 bolt center section and added 14 bolt axle tubes to it, making it a full floater with good ground clearence. He was a machinist by trade and I think he did a LOT of custom work on this axle to make it work.

The 12 Bolt will work just fine for most mild trucks. Add a C clip eliminator kit and replace the carrier with an aftermarket one ie. Detroit locker and Presto!! You are good for up to 36" tires depending on how you drive.

I Had a 12 bolt for a long time in my truck but when I went to 44" tires the axle tubes couldnt stand the stress of them big ol' heavy tires. I had a truss on it but it still couldnt take the punishment.


05-01-2001, 04:31 PM
what about a dana 80/70 out back, and what about ford's heavy duty axle, i don't know what its called, but it seems to be the same one on all their F250's and up

Power mad
05-03-2001, 06:01 PM
Hey all
Warn makes a full floating kit for the 12 bolt.
But at around $650 You might as well put a 14 bolt in.
I run 33's on the K5. D44 front and 12 bolt rear.
I've flogged her pretty hard and have had no problems yet.
I have a 14 bolt to put underneith as soon as I can find a D44 8lug at a good price. The 14 bolt has the same ratio as the 12 so I got lucky there.
I have an sm465 and np205 in it now. The addittion of the 14 bolt will make her almost bullit proof.
See ya

05-03-2001, 07:06 PM
My uncle has a heavy duty 14 bolt 3/4 axle. It is supposed to be stronger than the stock 14-bolt. I might consider bolting that sucker on.

05-07-2001, 01:53 AM
Anybody run a truck with a locker in the rear axle? Do them simulate posi or just lock both wheels completely? If they lock the wheels how is the turning affected? Seems to me like sharp turns would be kind of rough. I found one for $100, and one for $400. My guess is one rides a lot smoother than the other.