1/2 to 3/4 helpppppp

[MadOgre]

3/4 ton axles were a combination of a front Dana 44/Corporate 10 bolt and a rear 14 bolt SF or FF.

The front axles are 1/2 ton axles upgraded with 8 lugs and larger 3/4 ton brakes.

You can turn a 1/2 ton front axle into a 3/4 ton by simply swapping hubs and brakes

 

[MadOgre]

3/4 tons generally have stronger transmissions like the sm465 and the th400. Although 700r4s came in some 3/4 tons too

 

[Bkap725]

Awesome thanks for the help man

 

[HotRodPC]

You don't have to change the front axle to be a 3/4 ton conversion if it's not been said yet. Chances are you'll change it anyway though if you find a matching set of 3/4 ton axles. The only difference on the K10 and K20 front axle is rotors are 8 lug. So just change the brake backing plates and rotor and should be good to go up front.

But do keep your front K10 axle if you do use a 3/4 matching set of axles. This way you have spare axles, stubs and carrier. You might just need them.

 

[Greybeard]

Howdy MadOgre,
Right, I see where I made a mistake of omission. A 14bff out of a one ton will need the perches and one shock mount moved, but not if it's out of a 3/4 ton pickup. So it depends on the source of the housing (1 or 3/4 ton pickup or van, dually, or C&C).

I need to disagree that a 15" wheel will not fit the brakes on a 14 bolt FF. Of course, back in the day when the simple white (or black) steel wagon wheels where common there was no problem, aluminum rims I got no idea. But if they don't fit on the front then there is no point putting them on the back. I was happy with two different bolt patterns on mine. My rearends had the 3-1/2" x 13" drums IIRC which is likely the most common size brake system on them. The cooling fins on the drum made it larger so it was close, but it fit. I ran M-T tall Baja bias belted 15-15x39's on mine with a simple 6" lift and trimmed front fenders. However, today there is no point in using 15" rims because the tire selection for them is getting slimmer by the year.

 

[bucket]

Well all 3/4 axles are 8 lugs but Chevy did make some 3/4 ton 6 lug axles. It was like a light duty 3/4 ton or something....it wasn't a great idea. Anyhow...don't mistakingly buy them because they really are not any better that what you have. You are looking for 8 lug 3/4 ton axles.

First of all, the "light duty" 3/4 ton trucks were the '88-'98 body style, with IFS. Not used in the square body style. Second, a 6-lug 14bolt semi-floater is a hell of a lot better than a 6-lug ten bolt axle, no question about it. It's actually a good swap option to gain strength and keep the current wheels tires. But the OP seems to be looking for a bolt-in swap and probably needs better gearing too, which is why I didn't mention it in the beginning.

 

[bucket]

... A 14bff out of a one ton will need the perches and one shock mount moved, but not if it's out of a 3/4 ton pickup...

Not just one shock mount, both of them. Besides being mounted inboard of the frame, they are staggered in the opposite direction of the 1/2-3/4 ton mounting locations.


Oh, and 15 inch rims usually clear 3/4 ton front brakes. It depends on the manufacturer and the amount of backspacing. And steel rims of course. I don't think 15" 8-lug aluminum rims have ever been produced anyway.

 

[Rule_So_Hard]

First of all, the "light duty" 3/4 ton trucks were the '88-'98 body style, with IFS. Not used in the square body style. Second, a 6-lug 14bolt semi-floater is a hell of a lot better than a 6-lug ten bolt axle, no question about it. It's actually a good swap option to gain strength and keep the current wheels tires. But the OP seems to be looking for a bolt-in swap and probably needs better gearing too, which is why I didn't mention it in the beginning.

I was pointing it out because I see it a lot in craigslist where people have them listed as 3/4 ton axles. But I was under the impression they were still 10 bolt. I was wrong though. Learn something everyday.

 

[bucket]

I was pointing it out because I see it a lot in craigslist where people have them listed as 3/4 ton axles. But I was under the impression they were still 10 bolt. I was wrong though. Learn something everyday.

I was just mentioning what body style had a 6-lug 3/4 ton because they didn't have a front solid axle.

A lot of folks on CL don't have a clue what they are selling when it comes to axles. If I had a nickel for every time someone was selling heavy duty 3/4 ton 10 bolts...

 

[firebane]

In 88-98 there was no 1/2 ton that was considered a 3/4 ton. They had a optional package and the option existed through MANY several years of of the trucks being made.. The RPO is called F44.

The RPO code F44 was actually what the Big 10/Heavy Half name fell under and in later years was just considered a heavy half ton as they upgraded the rear axles, brakes and springs to allow heavier loads in a 1/2 ton truck.

And this is where you would usually find the 14B SF axles.

 

[Rule_So_Hard]

In 88-98 there was no 1/2 ton that was considered a 3/4 ton. They had a optional package and the option existed through MANY several years of of the trucks being made.. The RPO is called F44.

The RPO code F44 was actually what the Big 10/Heavy Half name fell under and in later years was just considered a heavy half ton as they upgraded the rear axles, brakes and springs to allow heavier loads in a 1/2 ton truck.

And this is where you would usually find the 14B SF axles.

Being thirsty for knowledge and realizing my original suggestions were inaccurate I did a little research and I found that the 88+ light duty 3/4 tons had the 14 bolt semi floater as mentioned above but had the same IFS differential as the 1/2 ton. I was unable to figure out which trans they had.

 

[firebane]

Being thirsty for knowledge and realizing my original suggestions were inaccurate I did a little research and I found that the 88+ light duty 3/4 tons had the 14 bolt semi floater as mentioned above but had the same IFS differential as the 1/2 ton. I was unable to figure out which trans they had.

There is no light or heavy duty 3/4 ton. You could have a 1/2ton or a 1/2 ton with F44 RPO code upgrading the back end to be more stought.

There were several variations of transmissions in the 88-98 era. 700R4 was a common transmission in the 88-94 years then they switched out to the 4L60E and later the 4L80E. They also had the NV3500 or NV4500 for manual transmissions.

 

[Rule_So_Hard]

I literally just looked at a GMC 2500 two days ago that had a 6 lug front axle. We pulled a bench set out of it for my brothers truck. That's why I was originally thinking they had light duty axles.

 

[Rule_So_Hard]

Okay I just shot a text to my friend who is a Chevy nerd and he says you could get a 1500 as a f44 and a 2500 as the same thing and they are identical.

--Edit, he says the only difference between the two is the rear springs. So a 1500 f44 had lighter duty springs than a 2500 f44. This information is purely what I'm being told and not anything I've confirmed myself.

 

[bucket]

In 88-98 there was no 1/2 ton that was considered a 3/4 ton. They had a optional package and the option existed through MANY several years of of the trucks being made.. The RPO is called F44.

The RPO code F44 was actually what the Big 10/Heavy Half name fell under and in later years was just considered a heavy half ton as they upgraded the rear axles, brakes and springs to allow heavier loads in a 1/2 ton truck.

And this is where you would usually find the 14B SF axles.

There is no light or heavy duty 3/4 ton. You could have a 1/2ton or a 1/2 ton with F44 RPO code upgrading the back end to be more stought.

There were several variations of transmissions in the 88-98 era. 700R4 was a common transmission in the 88-94 years then they switched out to the 4L60E and later the 4L80E. They also had the NV3500 or NV4500 for manual transmissions.

Incorrect, there were a lot of light duty 2500 trucks with 6-lug wheels and they were actually badged as a 2500 truck. Most I've seen were 2wd work trucks, but there have been several that were higher option trucks.

I literally just looked at a GMC 2500 two days ago that had a 6 lug front axle. We pulled a bench set out of it for my brothers truck. That's why I was originally thinking they had light duty axles.

Correct. That truck's rear axle is worth a few hundred bucks too, especially if it's a 4x4 with the wider axle.