axles

[cdm10700]

Have a 1994 gmc 1/2 ton 4x4 ....wondering if axles from a 1999 and up would fit under mine ..and did they make a 3/4 ton 6 lug .
Is there any difference in 1/2 to 3/4 as far as mounting .
Thanks in advance

[lindstromjd]

Also interested in same thing... subscribed

[57taskforce]

Are you referring to the cv axles or the rear end?

[cdm10700]

Front and rear axles and gears

[special-K]

I don't really know much about these front ends, but I believe they are interchangeable and the front 1/2t is no different from the 3/4t 6-lug. I think the only difference is in the rear axles. The 3/4t trucks got the 14-bolt semi-floating rear...the same rear as light duty 8-lug (9.5" ring gear). It will bolt in and is a great upgrade

[BigBlocksRule]

Make sure you get one from a 4x4, they're a couple of inches wider than 2wd. A lot harder to find, at least around here.

[lindstromjd]

Anyone know anything about the 8 lug axles? What all does it take to put 8 lugs in the place of 6? The whole 4x4 setup, front and rear axles...

[cdm10700]

Ok thanks ...I want to go 4.10 4.11 gears in and only find wm in 3/4 ton and 99 an newer 1/2 ton trucks ...I will be installing a 6in lift soon and thought it be easier to get axles then

[BigBlocksRule]

If you're wanting IFS 1-ton axles on the front, it's much easier to cut the existing front stub off and weld the 1-ton on. There's a "fish mouth" connection under your feet where Chevy put 'em together. Just cut your old front end in front of the weld so you have room to clean up the factory welded frame, do the opposite on the donor front, slide 'em together and weld 'er up.
Any rearend that's not cab-and-chassis is a bolt-up.

[54 jimmy]

everything from the knuckles out needs to be swapped with the 8 lug parts. they will bolt right on. the front diff needs to be swpped also to make the gear ratios match. your cv shafts will work they are the same. as far as the rear end you need to swap the complete rear and maybe the drive shaft or you might be able to change the rear u joint only. hope this helps.

[special-K]

Only the knuckles-out, huh? I always wondered. The front ends have a much wider track on an 8-lug, so that's all in the wheel offset? Makes me wonder why lifts are completely different.

[BigBlocksRule]

Completely different differential, 1-ton has a 9.5" ring gear. CV axles are NOT the same, 250/3500 are about 15% larger. Lower control arms are different, not sure about upper. Front ends are different stubs, have different differential mounting points, etc. I've seen guys try it, I promise it's much easier and doesn't screw with geometry if you swap the whole front stub. Hardest part is pulling the engine and front sheetmetal clip.

[57taskforce]

Originally Posted by BigBlocksRule

Completely different differential, 1-ton has a 9.5" ring gear. CV axles are NOT the same, 250/3500 are about 15% larger. Lower control arms are different, not sure about upper. Front ends are different stubs, have different differential mounting points, etc. I've seen guys try it, I promise it's much easier and doesn't screw with geometry if you swap the whole front stub. Hardest part is pulling the engine and front sheetmetal clip.

I've got no experience with half ton stuff in these trucks. I've had my k2500 for better than 10 years. I've got the heavy 8600 lb 3/4 with the 1ton suspension and running gear. It's got the heavy cast lower control arms 1 ton torsion bars and everything. I can further comment on the cv shafts in that they aren't even the same year to year. Mine is a march '98 build and it's got left over 97 axles in it. Only reason I know is because the lift kills the boots every 30,000 miles and when I get the new boots from napa the 98 boots are too small in diameter. So the 97 axles have bigger joints. If your gonna be lifting it you definitely want at least the 9.5" light 3/4 rear end. They come in the 6 lug variant. Be prepared to eat ball joints, inner and outer tie rods, pitman and idlers, hub bearings and cv shafts. I've got to go thru mine and replace at least a few of the above every 30,000 miles. Be advised. Make sue your hub bearings are in good shape. With 140,000 mine lost the passenger front wheel going down the road because the oe bearing came apart. Luckily my dad was driving it and got it off to the side of the road with out any major damage. $700 in front end parts for both sides later it was back on the road.

[special-K]

Good info. I thought they were completely different. I'd think a body swap would be the way to go...if your body is great and donor is not. Otherwise, I'd think finding an 8,600# 2500 or 9,200# 3500 would be the way to go. It's not like it's a cheap proposition swapping the whole front frame.

My '92 K3500 had 335k on it when I let it go. I had great luck with it. It was in need of ball joints for the first time. The only thing I ever did to that front end was idler arm every 80k or so. It was about due for it's 4th

[BigBlocksRule]

If you have the donor truck, it's plenty cheap
And it lets you build stuff that Chevy never built - like my 1-ton short wide dually 4x4 project!

[special-K]

Yeah, I used to wonder about putting 1t parts under a 2dr 6.5TD Blazer w/cargo doors when I was done with my '92 K3500. I didn't know the ins & outs of these truck, just drove it. I didn't know if it was a matter of shortening the frame or clip it, but I figured the front of the frame had to be different

Cheap or not depends on what you do or don't have and how you got it, and if you consider your labor's value or not. If I was staying with the same WB I'd stay with the complete 8600 GVW (C6P?) frame and lift the body off.

[54 jimmy]

sorry but they are the same. i have had the stuff side by side. the cv are the same depends on the manfacture. the lower control arms can be different they made them with a press in ball joint or a bolt/rivet in type. my 97 k1500 ext sb has 6 lug outers with 3/4 suspension. this is how it was ordered so you can swap vise versa. have done this before on my old 90 gmc 1500 swapped out front end parts with 2500 stuff no problems bolted right up and no issues down the road. 3500 stuff is totally different.

[cdm10700]

Ok thanks ....what gears do you have in your 97 ....would love to stay with 6 lug but 4.10 gears

[95 S_Trucker]

There are 2 types of 3/4 front suspension.

7200 GVW and 8600 GVW

7200 is 6 lug. 8600 is 8 lug

6 lug 1/2 ton will interchange with 6 lug 3/4 ton

8 lug 3/4 ton will interchange with 8 lug 1 ton.

That's all 4wd of course.

[special-K]

Originally Posted by 95 S_Trucker

There are 2 types of 3/4 front suspension.

7200 GVW and 8600 GVW

7200 is 6 lug. 8600 is 8 lug

6 lug 1/2 ton will interchange with 6 lug 3/4 ton

8 lug 3/4 ton will interchange with 8 lug 1 ton.

That's all 4wd of course.

Yeah, we've been talking K2500 8-luggers here, the 8600gvw, which is the same as the K3500. I've had both at the same time. Never had a light weight. I never considered them 3/4t. They can put whatever number they want on them for marketing, but to me it's a heavy half.

[57taskforce]

Originally Posted by special-K

Yeah, we've been talking K2500 8-luggers here, the 8600gvw, which is the same as the K3500. I've had both at the same time. Never had a light weight. I never considered them 3/4t. They can put whatever number they want on them for marketing, but to me it's a heavy half.

Couldn't agree more! My brother had a 7200 3/4 with 6 lug stuff. Just no where near the truck mine is.

[54 jimmy]

my 97 is factory 3.73 gears and it has a 12 bolt rear. not the 10 bolt that almost all the half tons come with. yes they make 2 3/4 tons fronts but you can swap everything from the knuckles out and it will work i have seen it done. front diffs will swap out too they just have different brackets rhat mount on the diff that go to the frame. the difference is the the 3/4 ton brackets lower the diff because they sit higher than the halfs do. this is done to help with cv angles. my bad on the cv shafts they do make bigger ones for the heaver 3/4 front but you can use either or the will work.

[95 S_Trucker]

Originally Posted by 54 jimmy

my 97 is factory 3.73 gears and it has a 12 bolt rear. not the 10 bolt that almost all the half tons come with. yes they make 2 3/4 tons fronts but you can swap everything from the knuckles out and it will work i have seen it done. front diffs will swap out too they just have different brackets rhat mount on the diff that go to the frame. the difference is the the 3/4 ton brackets lower the diff because they sit higher than the halfs do. this is done to help with cv angles. my bad on the cv shafts they do make bigger ones for the heaver 3/4 front but you can use either or the will work.

Are you sure its not a semi float 14 bolt?

The 12 bolt wasn't used since the early 80s

[rickpilgrim]

Interesting thread here. We own 5 GMT400 4x4 trucks in 1/2 std, 3/4(light) 3/4 HD and a 1 ton crew srw and a ex cab dually and our 3/4 light front end is not even close to the same as the half ton. The A arms are wider and more robust, the boots/joints/axles are noticeably larger I can't begin to think about swapping that to the 1/2 ton, the frames look bigger on the HD 3/4 and 1 tons.
And A arms being cast or welded means nothing either as the 3/4 light and 1 ton crew single have cast A arms and the 1/2, 3/4HD and dually all have the stamped/welded varity
X2 on a body/driveline swap and go 8 lug HD to get the heavier components.

[BigBlocksRule]

2500 and 3500 came out with forged lower control arms in about '97. They're definitely forged, not cast.
I can promise you guys, if you want to swap to a heavy duty front (3500), it's soooo much easier to cut the entire front stub off and swap it with the heavy one.
I want to find a 2-door Tahoe plain-jane and swap the big front and add a semi-floater out back for a trail rig. Air and electric lockers are available for the big 9.5" front diff, you can't even get one for the half-ton stuff because it'll blow up the first time it spins and gets solid traction with a lot of power applied.