rearend interchange

[turbotank]

Does anyone know what sort of problems I might face swapping in an 8 bolt 3/4 ton rear from a k2500 suburban into a 89 1500 suburban?????And is 250 a good price for the rear plus springs and wheels?Thanks.

[youngin']

Um... I may not know alot about all the tranksfering and crap, but for a complete rear end- with springs- PLUS WHEELS----FOR $250 That's a HELL of a deal anyday! At least in California.

[turbotank]

Yeah,thats what I was thinking,it looks like a 14 bolt 8 lug. On a k2500 suburban. I know that this is a bulltet proof rear as Im told,and I am definitely interested in it,but want to know if I will have to do any crazy modifications to it. Like will it take the stock driveshaft/u-joint? The springs look like they bolt up in the same location as the 10 bolt I have in my suburban,but I need to make sure b4 I buy. I wonder what kind of tow capacity this would give me also. Anyone know the other differences between 3/4 and 1/2 ton suburbans??Thanks

[turbotank]

nobody knows?

[WarBeard]

Should mostly bolt right in...You will need a conversion u-joint to a 1350 yolk
Bigger u-bolts and spring plate the 3/4ton springs are wider i think, and wont fit into your 1/2ton spring hangers on the frame......And of course 8-lug wheels!

One major thing to remember about the 14 bolt axle's...Suburbans had two options for 14 bolts...
A full floating and a semi floating...The full floating one is the one you want, it's the one everybody talks about.
The semi floating is a c-clip axle...both have 14 bolts on the diff cover.
4x4 suburban's (73'-91')Never came with a 14 bolt full floater from the factory.
Full floaters can be identified by the big hub protruding from the center of the wheel.
Semi floaters do not have this.
14 bolt semi floaters are a strong axle but the full floater is the top dog!

[turbotank]

the spring plates just unbolt from the frame,right? It does look like it has a hub sticking out of the wheels. Is there any other positive id? Can I get that ujoint at Napa or something,or does it need to be custom made?

[WarBeard]

The spring plates are what the u-bolts go through on the axle.
The u-joint can be had at napa its pretty common.
Besides the hubs look around the yolk on the axle it should have 6 bolts going into the axle so that the pinion can be pulled out...... the semi floater does not have this.
The 14 bolt semi floater can be converted to a 6 lug by changing the axle shafts then you could have a really tough 6-lugger.

This picture is a 14 bolt full floater..Its the one you want



This is the semi floater its an OK axle but i wouldn't go through all of the trouble to install it when full floaters are plentiful

[turbotank]

Thanks for the pics!! I got a chance to go back to the yard today,and it looks like this is a semi floater. That sucks,oh well. If I run across another one that I can get(might be another in this yard),do I need to change the spring hangers?Thats what I meant to say when I was talking about the spring plates.Thanks for the help

[DirtyLarry]

Originally Posted by motomech

4x4 suburban's (73'-91')Never came with a 14 bolt full floater from the factory.

Hey Mototech,

Actually, they did. 1973 through 1980 ¾ ton subs all had 14 bolt full-floaters. The 9.5” 14 bolt semi-floater came on the scene in 1981 as the standard ¾ axle behind small block engines. You could still have a full-floater in a 2wd sub up through the time that body style ended in 1991 but only in a big block, which big blocks could only be had in 2wd. By never, you were probably thinking of big blocks. Big blocks were never available in 4x4 Subs until the GMT400 body style came out in 1992.
Not bashing…..Just talkin cool GM trivia

[WarBeard]

MY bad ,I didn't think they came in the 4x4 burbs no matter what engine.....
O well learn something new everyday

[turbotank]

So,a 1973 8 bolt rearend should be the full floater right???

And what are the pros and cons of the 14 semi float,Im only saying cause it is a decent price,and I need a rearend in my suburban,as the 10 bolt is shot.Thanks for the replys

[turbotank]

Just a quick question about something I've noticed with this swap... Would I need to shorten my driveshaft with the full floating rear? Or could I get the driveshaft from the donor,and stick it in my tranny? Does the semi floating require shortening?

[DirtyLarry]

Yes, a ’73 8 lug axle from a Suburban would be a 14 bolt full-floater. The semi-float 14 bolts are an okay axle for a driver. If you plan on running big tires or doing any serious off-roading I would recommend the full-floater hands down.

And you will need to have the rear shaft shortened once you swap in the full-floater as the pinion is much longer than your 10 bolt which requires the shaft to be shorter. Or, like you say, grab the shaft from the donor if you go the 14 bolt semi-float route. The 73’ Suburban shaft will not work in a later Sub.

A couple years ago, I swapped out a 14 bolt semi-floater for a full-floater in a buddy’s 1988 Sub and had to shorten the shaft. You will also have to get creative to make the emergency brake work as well.

Full-floater



14 bolt semi-floater that was removed.

[turbotank]

So,will I need to shorten my driveshaft to do the semi float? How much does shortening the driveshaft usually cost to get done anyway?
My suburban is just a 2 wheel drive,but I plan on hauling some semi heavy stuff,and am tired of the junk 10 bolt that is under there,and want to go overkill on the rearend,so I don't have to mess with it for years.
Quick question though...is a 73 burban still on the older body style,the rearend I saw out of the 73 is a truck,will that fit? I think that was the first year of that model,I dunno.

[turbotank]

Well,change in plans. I got layed off from my job yesterday,and now I am in a spot. So buying that axle is off for now. That sucks bigtime. So,because of my situation,does anyone have any axles that they don't care about,10 bolt 12 bolt anything? I can't pay much,cause Im instantly broke.Thanks

[turbotank]

Okay,now that Im broke like I said b4,I need to get creative. I have a couple of choices. My dad has 2 12 bolts that he will give me,they have been in the weather for quite a while on some blocks. He says he thinks that he "stripped" the gears. But the differential cover hasn't even been off of one of them.Now,if I can get them up to snuff,they may work as they came out of an 82 chevy truck. Okay,since they look rough,next wild question. He also has an old ford(I know) church van,and I could probably get the rearend out of it,and as far as I know it was fine b4 it was parked. Anybody ever tried this,and what problems could I see? I wouldn't even consider either of these options,but you know how necessity is.Thanks

[turbotank]

Does anyone have any input for me,I need to get my suburban up and going and was hoping to get some advice.