What axles and tcase should I go with?

[65malibu]

I am looking at beefing up my axles and replacing my np203. I have a 72 blazer with Dana 44 front and rear. I have a 350ci/350hp motor with a th350. I will more than likely be running 35's. Mainly around town driving, but a few trips a year to the mountains of colorado for weeklong camping/offroad trips with my jeep buddies.

Should i just stick with Dana 60s front and back and an np 205?

Or should i be looking for a newer model chevy truck 2500 to rob the running gear from? What are the axle names i should be looking for? What transfer case should i look for? What year models of trucks/tahoes/suburbans should i be searching for?

Sound off on your experiences/preferences please. Thanks.

PS. I also posted this in the 4x4 section in hopes of catching more information from other forum members that might not come to the blazer section.

[Firebirdjones]

Really depends on how much punishment you plan.

The stock front Dana 44 and 12 bolt truck rear can be beefed themselves without swapping to something else for alot less work.

I do mild off roading with mine but it's primarily a daily driver. For what I do the stock stuff is plenty durable around Arizona. It goes anywhere I've ever cared to take it.

As far as the 205 transfer case, I think the only complaint from some people is not enough gear reduction. 1.96 isn't much, but I find it works fine for even slow crawling (in my case) with 3.07 gears and a 3.06 first gear, it's creeped up anything I wanted to try.
What most would agree on is the transfer case itself is probably one of the toughest factory peices out there.

Just depends on how involved you want to get.

[Mike C]

Cross-post...

Look for my response in the 4x4 section.

[65malibu]

i did get lucky and found a 78 3/4 ton truck and robbed the axles and transmission/tcase off of it. The rear was a 14b (i assume it is a full float?). The front is unfortunately a d44 (i think). the tcase is an NP205.

So should i beef up the guts of both internally? add kingpin knuckles to the d44 front and do the high crossover steering?

I assume my current tcase is an np203 because i think it only has 4hi, 4lo, and N.

[Firebirdjones]

If the rear differential you grabbed out of a 78 chev has a 14 bolt cover, than that's the GM manufactured 14 bolt that started production in 73, used in 3/4 ton and 1 ton applications.
Full floating axles, 10.5" ring gear, and a large 1.75 pinion diameter. Tough rearend, according to Randy's Ring & Pinion, you can run up to a 44" tire on this rearend without fear of breaking. It has a a continuous 6,300 ft lbs. output torque rating.

If you found a Dana 60, the cover is shaped close to the same as the 14 bolt GM but the cover would have 10 bolts. The ring gear diameter is a smaller 9.25", pinion is smaller at 1.625", and it only has a 6,000 ft lbs. torque rating and that's for a short duration,,,not continuous. That's also for the HD version of the Dana 60. The standard Dana 60 has a 5,500 ft lbs. torque rating which is again,,,,short duration, not continuous.

Stock for stock, the GM 14 bolt is a much stronger unit.

[65malibu]

awesome. Thanks so much for the replies guys.

i am learning a lot here. this is my first 4wd vehicle. I have dabbled in mid 60's muscle cars and tri-five chevys. I definitely dont know half of what i thought i did.

the rear axle i took from the 78 3/4 ton is a 14b with the five bolts on the pinion yoke. so that's a great axle right?

i will post some pics of each axle. please help me identify/confirm what i have. Thanks so much.

Front Axle Dif Cover


Front axle steering knuckle


Front Axle Yoke


Rear Axle Dif Cover


Rear Axle yoke

[Firebirdjones]

Yep, that's a GM 14 bolt built by the Saginaw axle division of GM.

The other appears to be a Dana 44.

Nice to see another muscle car enthusiast here. That's all I've dabbled in for 30 years. Still have a 56 Nomad, 72 SS 454 chevelle, SCJ mustang, 70 Formula, etc...
I love the old trucks though and have always had a couple of them around.