Opinions Wanted - 1972 C20

[lks dcvn]

I just picked up a 72 C/20 and it came with all the parts to swap over to a 5x5 front disc and rear drum axle.

I won't be doing any heavy hauling or towing with the truck (just normal runs to Home Depot, Lowes, etc.).

My question is - should I keep the 8 lug 3/4 ton axles or should I swap over to the 5 lug stuff? I would like to hear opinions on this:

For vs Against the swap
Cost differences between the two for maintenance, etc.

The truck will be used year round (even in the snow) for driving. It runs and drives great now - (just has some rust to fix here and there).

Thanks for your input everybody. Looking forward to hearing what you have to offer.

Happy Holidays!

[Gray Ghost]

If you have ever had trouble with the rear brakes on a 3/4 ton you'd swap them out in a hurry. While those 14 bolts are very strong, they are problematic for everyday drivers. You have to remove the rear axles to do the brakes!

If you are not going to haul much more than the normal person, I'd swap them ASAP.

[Sinister]

Originally Posted by Buffalo Elk

If you have ever had trouble with the rear brakes on a 3/4 ton you'd swap them out in a hurry. While those 14 bolts are very strong, they are problematic for everyday drivers. You have to remove the rear axles to do the brakes!

If you are not going to haul much more than the normal person, I'd swap them ASAP.

I had a '72 C-20 and it had a Dana 60 rearend, no need to pull the rear axles when doing the brakes...

[lks dcvn]

Here is what I am working with...appears to be a corporate 10 bolt in it now...

The first 2 are what is on the truck now...
The 3rd pic is what came with it (3.08) 5x5 axle (12 bolt)
The 4th pic is my second option for the rear - 5x5 (no idea on gearing) (12 bolt)

[uncle]

The lowest gear (In Numbers) for the 1st rear is a 4:10,so that could be one thing to consider if you drive over 60 often. You can pull the cover on the other 12 bolt to check gear ratio or there is a 3 letter code on the p/s axle tube between the chunk and perch.

[LockDoc]

-
Here is what Uncle is talking about on the 12 bolt. Not sure if the 10 bolt has the same codes or not. TDE is the code on this one. Find the code and look it up here:

http://www.americanclassic.com/paint.htm

If you don't know the year just keep going through the years until you find the code #. Some of them have two letters and some have three.

[69halfton]

If its just a daily driver...and your not hauking anymore then you'd feel comfortable hauling with a 1/2 ton, id swap em.

disc brakes are real nice for stopping, fast, as opposed to those 3/4 drums.

also, 5 bolts give you WAY more options for different rims. I.e nice for summer...and winter rims for ...well winter.

just my 0.02

[Longhorn Man]

first, lets not call it a 10 bolt, that gets too many people thinkgin of the car/later light truck 10 bolt rear. Lets call it the eaton, or the corperate rear.
There were never any 14 bolt rears installed in the 67 - 72's.
Pulling the shaft and hubs on a HD rear is not that big a deal, it is a small price to pay to have a much stronger rear.
However, As stated above, a 4.10 is the best you'll find in your rear in the eaton diff. The 12 bolt is most likely a 3.73 if it is out of a 3 speed manual, or a 3.07 if a 4 speed or automatic truck. This will make your truck much more tolorable on the freeway, esp if it is the latter (I recomend the 3.07 personally)
If your truck is no longer a heavy hauler, then i wouldn't hesitate to swap in the lighter duty parts. The brake parts are cheaper, the diff parts are still avalible which means MUCH cheaper if you ever need to dit into it, your MPG will be better if you get on the open road much, the wheel selection is greater if you want to dress it up a bit, and the tires are considerably more affordable.
However, if your truck is still gonna be a truck, a 3/4 ton is much more cabable than a 1/2 ton.

[brianthelion02]

Once a c-20 always a c-20!!!!!My 2 cents!!!!!!!

[jeffspower]

Unless you are going to be doing alot of highway driving & log a bunch of miles every year, I'd leave it alone. Your '72 rear uses the same rear drums & brake parts as the '73- up 14 bolt rear. While not as cheap as the 5 lug stuff, all is readily available. When you consider all the hours of greasy knuckle scraping work, different brake hoses, steel lines, proportioning valve & MC for front discs... it wouldn't be worth it for a short trip parts hauler IMO. Used 16" aluminum rims are not hard to find. "88- up steel rallys look great for cheap. New truck aluminum takeoffs with tires in the $650- 750 range isn't bad either. I bought a set of steel rallys with rings, caps & lug covers for $150. Another $150 to blast & paint them, and new Bridgestone takeoffs from ebay were $220 that I picked up an hour away. That was a smokin deal on the tires

[jeffspower]

Ooops- scratch the steel line & prop. valve swap... you already have discs

The MC is different though.