1972 K20 Axle swap

[DJ_]

Well hi everyone, I got a 1972 k20 that I just got and I got a question. My question is can I swap 2008 super duty Axles under my truck? Because the previous owner of my truck took off the 3/4 ton axles and put 1/2 axles on my truck. So I was thinking instead of putting the original set up on my truck, i should upgrade my axles to super duty axles so i can have disc brakes all the way around and I believe 08 axles that I can get my hands on, the front axle is a dana 60 and the rear end is a sterling 11.25 with a detriot locker.

The story on My truck is that I had a 1969 c10 that i got for $800 buck from the original owner. It was sitting since 1989, I got it running and driving, it had a 250 inline 6 with a sm465, 12 bolt with a posi. My plans was to lift it something like a prerunner but someone offered me 6k for it so I sold it and got this truck.

My Current truck is a 1972 K20 4x4, the previous owner swap out the 350 to a 5.3 ls motor with a 4l60e and np241 transfercase. Ill try to post some pics of the truck this week.

[Frank_Zappa]

Are the 2008 front and rear super duty axles coming from the same vehicle? As in are they a matching set?

[DJ_]

Originally Posted by Frank_Zappa

Are the 2008 front and rear super duty axles coming from the same vehicle? As in are they a matching set?

thanks for the reply! and Yeah there coming off my family/friends wreck truck. I know i would have to cut off where the coils go and weld in the plates for the springs. I just want to know if someone done this before.

[Dieselwrencher]

You might get a tape measure and measure those axles. They are super wide to be putting under one of these trucks so the tires will stick way out there. Plus those axles have a metric bolt pattern and will require 8 on 170mm bolt pattern. If it were me, I'd see about keeping that coil spring suspension in the front if I was going to make the swap. Those ride really nice.

[52napco]

The ford.axles would be a pain To put under a leaf spring truck since they
Have a bunch of.material cast into the housing for coil spring and trailing arm
Mounting. Also unless your truck has the 1988-1991 241 case with passenger
Side drop the ford axle is on the wrong side. Not a good option

[57taskforce]

Not to mention the lack of king pins in that front 60

[DJ_]

Originally Posted by 57taskforce

Not to mention the lack of king pins in that front 60

thanks for the advice guys! So you guys think its better to put a 14 bolt and dana 44 8 lug back under it? I just don't like the 12 bolt that the previous owner put back in the truck because i don't want the c-clips to break and see one of the rear wheels pass me well I'm driving LOL. Im gonna use the truck as a truck my plains are in the summer to haul a 25ft boat and in the winter to haul 24ft inclose trailer to go the the dunes. maybe time too time take it through some trails but nothing nasty.

This is how my truck look when i bought it but ill try to post a picture of the truck sometime this week with the front end back on.

[52napco]

Since it has a 4l60e trans i would find a set of cucv axles from military K30
4.56 gears and a detroit in the rear.front dana 60 is bolt in but spring perches
Will have to be moved.which side is the output on the transfer case for front
driveshaft ???

[jeffahart]

Unitbearing hub alert.... Unitbearing hub alert... You get the high pinion, but you also get unitbearing hub(I think, I'm pretty sure), plus the hassle of driver side drop(assuming you have a passenger side 241). Got to weigh the options.

What he... 52Napco said ^ ... if you can find a good axle set at a fair price I'd go this route. If you drive the vehicle on road you might like the idea of a good strong ebrake/parking brake. I kept rear drum on my 14... I like to leg press my parking brake!

[DJ_]

Originally Posted by jeffahart

Unitbearing hub alert.... Unitbearing hub alert... You get the high pinion, but you also get unitbearing hub(I think, I'm pretty sure), plus the hassle of driver side drop(assuming you have a passenger side 241). Got to weigh the options.

What he... 52Napco said ^ ... if you can find a good axle set at a fair price I'd go this route. If you drive the vehicle on road you might like the idea of a good strong ebrake/parking brake. I kept rear drum on my 14... I like to leg press my parking brake!

Yeah its a passenger side 241, but i found a set of set of axles on craigslist for $600 they have 410 gears.






Yeah the 1/2 ton axles in my truck are 3.73 gears. But I haven't driven my truck yet because Ive been working a lot so I haven't pick it up from my friends/previous owner house yet. But I already think that 3.73 is too much of a highway gear for towing, so I was gonna make it 4.10s when I change the axles.

[52napco]

if you are going to run a taller tire and the overdrive then 4.56's with a 35" or so would be spot on but the 4.10's are fine also

[jeffahart]

OK, I had it in my head you were targeting the Superduty axles for a bigger axle/ high pinion . You can also look into a D44 disc front, this and the 10bolt are common. But you can do some quick research on D44 vs 10bolt so you feel comfortable with what your getting. Your truck probably came with a D44 8 lug.

I feel like, if the 10bolt really is in good shape and a drop in without having to rebuild then maybe a good deal. I also feel like the corp14 is along for the ride... kind of a throw in extra as they are so plentiful. But if it's a junkyard dog you may be into it for a tear down on either axle.

I'm always hearing about how everyone gets cheap axles. But I set out looking for a replacement front for my truck. I could not find a decent D44 for a good price. Lots of miss communication for me before running out and looking at axles. I got frustrated, and impatient. I had the 1970 Open knuckle drum brake axle. It needed to be gone through. So I decided on a disc axle(after spinning my wheels on a disc conversion for that axle, because you figure hey it's open knuckle like the new ones should be able to upgrade it to disc... anyhow different story). Point is, you really got to look at the axle your getting. It may not be cheap if you have to go through it.

I think the main thing for you is to get the gears you want with front disc. In any axle combo of:

Rear: D60, eaton, corp14
Front: D44, 10bolt, D60(a bit harder to locate these days off the GM 1tons)

These will probably be the most common with easy hookup to get you on the road! Plus you have more chances of getting running axles, with the gears you want, without spending bucks after you buy the axles.

Also, if you figure your getting a real good deal and only need to swap gears... make sure you are on the right side of the carrier break on whether you are gearing up or down.

[jeffahart]

Originally Posted by 52napco

if you are going to run a taller tire and the overdrive then 4.56's with a 35" or so would be spot on but the 4.10's are fine also

I really like 4.10s I think it's good compromise also! I'm still running 4.56s with 33s. LOUDness

What... what.... huhhh what..... I'm going deaf!!!!!!!!

[DJ_]

thanks guys for all the help, the truck right now has 33s but I'm thinking about going to 35s but if I stay to 33s I think Ill be fine with 4.10s. Im thinking about getting those axles off craigs. if I have to go through them then that gives me a chance to put a Detroit locker in them.

[Dieselwrencher]

Originally Posted by 52napco

Since it has a 4l60e trans i would find a set of cucv axles from military K30
4.56 gears and a detroit in the rear.front dana 60 is bolt in but spring perches
Will have to be moved.which side is the output on the transfer case for front
driveshaft ???

The way you have this written it looks like you're saying the spring perches need moved on a D60 to put them in the front of a 67-72. Did you mean for the rear end?

The spring perches don't need moved to put a chevy D60 front in a 68-72 4x4. I've even put dodge D60's in these trucks without modifying the spring perches.

[jeffahart]

Also, the 14bolt is an easy convert to disc, you can get the brackets from a few different vendors. Offroad design has caliper brackets and spacers and bolts in a kit.

I'm always tempted to go rear disc... but I really love the stiff ebrake I'm getting with my rear drum!

[57taskforce]

Originally Posted by Dieselwrencher

The way you have this written it looks like you're saying the spring perches need moved on a D60 to put them in the front of a 67-72. Did you mean for the rear end?

The spring perches don't need moved to put a chevy D60 front in a 68-72 4x4. I've even put dodge D60's in these trucks without modifying the spring perches.

Took the words right out of my mouth about the 1st gen dodge 60s. That's always a nice little secret when it comes time to go Chevy 60 hunting.

[jeffahart]

Yea, if I had to do it today I'd probably try to go the Dodge route, the GM 1ton prices are way out of line.... were out of line even when I bought mine a couple years ago. I think there is a slight offset on the perches to GM spring location. I saw once on the ORD site they make bushings to support the Dodge to GM D60 swap. I think. But 57Task has probably done the swap so, probably you would be OK.

I would think hard about getting(or at least researching) a D60 front for sure, while you have your hands on it! Lots of info on this site.

[Dieselwrencher]

The dodge 60s are a little narrower too but nothing a nice spacer won't fix. I have one from a 93 Dodge in my 72 K30. The spring perch width is around 1/2" narrower than a chevy D60F if I remember correctly.