K5 axle swap on a cj5

[BigAl77cj5]

howdy from ohio.
Just found a set of half ton chevy k5 axles. they come with a set of old 38 inch tires. I am planning on doing a complete frame swap on my cj soon want to upgrade axles. have a AMC 304 /T-150 /Dana 20 . would the blazer axles last with the 38's on them. I know 38's are huge on a 5. but I have seen it done and I am not apposed to doing some body trimming as at this point most of it has rusted away anyhow. lol. want to build somthing that will look mean and back up its looks.

...forgot to mention the cost of the axles with tires and rims is $375. would the swap be worth doing? and I know I have to outboard the front springs. working on a plan for that.

 

[Old Dog]

depending on what year, the best you can hope for is a pair of Dana 44 's.
38's are really pushing the axles a little over there max. they won't hold up to heavy wheeln, but would be ok for the street.
They are also built to be SOA is that what you were planing?

 

[pwrwgn]

Depends on the vintage of K5 axles. After about 77 they have a GM 10bolt front and rear. Not a bad 1/2 axle but not much support in the aftermarket. Both the 10 bolt and the 44 are marginal with 38's. You can get alloy shafts for the 44 and if you run mostly mud or sand they will survive. If you run rocks and are set on 38's I'd keep looking for a 60. Rear 44's and 60's are plentiful in Dodge, Ford and Jeep trucks. Most of the 60 rears are 8 bolt but you occasionally find a 5 bolt one in a Jeep or Ford.

 

[BigAl77cj5]

Yeah I was planning on doing a soa and going to build heavier spring packs for it. Don't plan on doing any rock crawling. Mainly just ohio mud and woods running. Plus might take it to town once and a while.

 

[imbobbbb]

A k5 will have either a 10 bolt or 12 bolt rear depending on the year.....neither is worth swapping into anything and are too weak for 38's.The stock ratios were 3.42,3.73,or.......3.08.None of them will work very well with 38's and its not worth the cost of gearing up when there are so many better rears to choose from.

 

[cj5grandnationalturbo]

I'd say do it. Those axles with 38s on them in the blazer would of been a big push. Your jeep ways about 1/4 of the blazer those axles were in so they should be ok. Then there is the fact you won't be on rock so you should be fine.

 

[Old Dog]

A k5 will have either a 10 bolt or 12 bolt rear depending on the year.....neither is worth swapping into anything and are too weak for 38's.The stock ratios were 3.42,3.73,or.......3.08.None of them will work very well with 38's and its not worth the cost of gearing up when there are so many better rears to choose from.

Good point about them not being worth sinking any money into.
I've seen (and owned) a lot of old chevy 1/2 ton trucks (same axles) with 38's,
and it doesn't take much to break them.

 

[BigAl77cj5]

Don't know for sure that I will stick with the 38's but I am going to get the axles. I talked the guy down to $250 and he is going to give me the chevy leaf springs too. They are the same width as rear cj and yj springs so more springs that I could use to mix and match in my pack. I will probably end up running some 35's or 36's

 

[hoerner7]

I did the swap with late 70's chevy 1/2 ton axles. I went with 36s and havent had any problems. I only have a 6 cyl though. At least youll get the hard part done by swapping those in. Later if you want to go to bigger axles its a quick swap.

 

[BigAl77cj5]

I did the swap with late 70's chevy 1/2 ton axles. I went with 36s and havent had any problems. I only have a 6 cyl though. At least youll get the hard part done by swapping those in. Later if you want to go to bigger axles its a quick swap.

Yeah that was another thought I had. I am sure I might run across a set of 3/4 tons to swap in later down the road so everything would be ready to go.

 

[60wcj5]

Got a 78 blazer with 3/4 ton axle swap. (8 bolt wheel 12 bolt housing) In this era the only difference between half ton and 3/4 ton front axle is the spindle and rotor. Mine is sporting a six inch on thirty fives. I have gone through more than one front axle but every time my rig was put through unreasonably severe punishment. Also carrying the weight of a big block swap. If your just playing around and looking at budget you will be fine. Extreme wheeling u are asking to get hauled out. Just my 02.