HO72 rearend rebuild
 

Ok Im new to this site, so if Ive missed an old post, please excuse me!
I have a 71 K20 4x4 with an HO72 1 ton rearend. My bearings are starting to go, and now fluid is spraying out of the yoke so I need to do a rebuild. I would go with a 14 bolt, but I want to keep the suspension original, and mine has the optional Detroit Locker, so for $$$ reasons, it makes sense to keep what I have. My question is:
I have seen rebuilt kits for prices that range from $400 up to $800.....does anyone know who has the best price on a high quality rebuild kit for this 3rd member???
thanks,
Blake

Re: HO72 rearend rebuild
 

If anyone has the stuff it would be Randy's Ring and Pinion in Everette, WA. Phone 1-800-347-1188. Shouldn't be too far from you either. WES

Re: HO72 rearend rebuild
 

Yes I called them and they are very expensive. They sell a kit made by yukon gear, and Ive seen the exact same kit online for up to $250 less than Randys sells it for. I was just hoping someone may know who has the best price for the kit, so I can spend a little less time searching.

Re: HO72 rearend rebuild
 

if you have a ssingle rear wheel HO72 I would swap it out. It isn't original anyways, so originality isn't an issue, and the 14 bolt is not only better, but you can actually get parts for it.
Go try and find drums and shoes for it.
The 3/4 tons came with HO52.

Re: HO72 rearend rebuild
 

The 14-bolts are no better.They are both equally great rears that combined have rolled trucks on down the road for 60 years or so.You should try Napa.That`s where I get all my parts.I think you have a HO52.Why do you think it`s an HO72?They are the same,all but the brakes and wheel bearings.Other than staying original,it`s nice to not have to move the spring perches and shock mounts which is required on 14-bolts.I love those No-Spins!!

Re: HO72 rearend rebuild
 

I have friends with 14 bolts and they all tell me what they have is no better than what I have. The only bad part about the 10 bolt is buying brake parts. They are available, but very expensive...but I have been reading some chats online and some guys have said that a disc brake kit for a 14 bolt will work on a 10 bolt, which would be nice. Pulling my third member out for a rebuild and adding disc brakes sounds easier than changing spring perches and shock mounts

Re: HO72 rearend rebuild
 

I'd be very interested to read more about this disc brake conversion for the Eaton.


(BTW my burb has been on jack stands for a couple months now, since I can't find one brake part. So I can attest to the availability of parts).

EDIT: I did a little search and found this website: http://www.blackbirdscustomtrucks.com/index.html
They have the conversion kits, and for what they are selling it seems pretty reasonable.

Re: HO72 rearend rebuild
 

yes, from what Ive been reading.....apparently the 14 bolt disc brake kit will fit the 10 bolt but you have to trim the caliper mounting bracket. Sounds pretty minor to me, especially if it turns a $600 brake job into a $200 brake job!

Re: HO72 rearend rebuild
 

I`m planning a disc brake job on the 4.10 No-Spin i have.The 14-bolt kit can be used and I wonder why you couldn`t use 14-bolt drum brakes.

Re: HO72 rearend rebuild
 

FYI, an HO72 or HO52 may have 10 bolts on the inspection cover, but that does NOT mean it is a 10 bolt. Asking for "10 bolt" parts will not get you what you need.

Just so you do not accidentally order the wrong parts.

Re: HO72 rearend rebuild
 

West coast differental had the kit availabe the last time that i needed a set. They were not cheap but the kit fit correctly.

Re: HO72 rearend rebuild
 

Im only referring to it as a 10 bolt in conversations about comparing it to a 14 bolt....but thanks for the clarification for those that may not be up to speed on the subject.
West Coast Differential huh? I will have to check the pricing and compare to what I have seen so far. thanks!

Re: HO72 rearend rebuild
 

anyone else have any input on a budget friendly rebuild kit for this rearend? The prices seem to be all over the place

Re: HO72 rearend rebuild
 

Randys Ring and Pinion ended up being very helpful with sourcing the rebuild parts I needed, but Im still looking for a good source for a disc brake swap on my HO72. Anyone have any good suggestions?

Re: HO72 rearend rebuild
 

http://www.blackbirdscustomtrucks.com/

At least one of the 14 corp kit (there are many styles) will fit your HO72. Give them a call.

Re: HO72 rearend rebuild
 

i would really have to push to do the swap for the 14 bolt. every eaton ive ever seen has leaked oil out the yoke seal, there are no parts available and there are only 2(?) ratios available. slow and slower. its not that bad to swap in a 14 bolt as long as you have a welder. but if you want to keep the old eaton in it, go to napa.:m5:

Re: HO72 rearend rebuild
 

a lot of trucks came with the 4.10 gear which is a good ratio on a 3/4 or 1 ton truck unless you have a diesel. why you would want any less than a 3.73 on a 3/4 ton truck is beyond me. i have a third member for my 72 burb so i can do away with that 4.57 final drive. i figure it will give me a 300rpm drop at 60mph. only other thing i will want long term is an overdrive (borg warner - saginaw unit in my case). having an overdrive will make a huge improvement regardless of gear ratio. i have some royal purple 80w-90 gear oil for my ho52 when i do the swap.

as for a rear disc swap......i'll just keep my stock drums rather than put on an aftermarket kit. i like aftermarket parts (poly bushings, braided hoses, etc), but if the factory made something comparable (or better) i go that route. 2000 and newer GM 3/4 and 1 ton trucks have rear disc brakes and they will have a proper mini-drum e-brake that is much better as a parking brake because drum shoes have more surface area and it takes less pressure to engage the brake linings. also, it means you have a fresh parking brake for the life of the vehicle (unless it falls apart from age) and you don't have to fight with an e-brake cable when you do pad swaps. the 87-88 dodge daytona had a lousy rear disc setup with caliper e-brake that was prone to issues and then in 89 chrysler came out with the idea for the center of the brake rotor to act as a small drum e-brake. some other factory manufacturers have followed suit, but the aftermarket doesn't always invest the millions that auto manufacturers do. i'd rather have factory GM 8 lug disc brakes where all the parts were intended to go together rather than some kit. getting replacement parts are more convenient too.

Re: HO72 rearend rebuild
 

Guess I better lock mine up, it's a rare one... I've owned it nearly 33 years and it doesn't leak.


Ah, I shouldn't have said that, now it will start dripping next week. :lol:

Re: HO72 rearend rebuild
 

I took mine to the shop and they tore the whole thing apart, inspected the bearings, and told me they wouldnt feel right charging me nearly $700 for a bearing kit cuz my bearings still looked great! The yoke had bad grooves which was causing my leak, so they sold me a nice used one, and machined my pinion plate which was warped and also leaking. They put it all back together and reset the backlash and Im good to go! ready for another 300k miles! I love the 4:10 with the Detroit locker, and they told me mine is one of the cleanest theyve ever seen, so Im gonna stick with it.
I do agree that a GM OEM type setup is the way to go for the disc swap, so I guess the search is on for a factory 14 bolt disc setup so I can get the brakes and associated parts, as well as the proportioning valve. Anyone know if I will need to use a master cylinder and/or booster from a newer truck also? I want it to stop properly, and I want to retain a good working parking brake

Re: HO72 rearend rebuild
 

Again, I will say call Blackbirds. Tell them what you want. They will know.

Re: HO72 rearend rebuild
 

I sent an email to Blackbirds, so Im sure I will hear from them soon. Has anyone of you done this swap solely from junkyard parts? If so, whats the donor truck to look for?

Re: HO72 rearend rebuild
 

Capev86, that style is nice but can be a PITA to work on. Many different vehicles use that stye. Here is something to keep in mind. You can use 1978 cadillac eldorado disc brake calipers that have a park brake built into them for the disc brake swap. They are a little more expensive, but atleast you will have a park brake. Also you could purchase an adjustable proportional valve and adjust it to your braking style/needs.

Re: HO72 rearend rebuild
 

Eldorado calipers huh? What year/make rotors can be used with those?
I called Blackbirds.....they wanna sell me their complete kit for almost $600, but wont tell me what year/model truck all the "off the shelf" parts go to untill I buy the kit.....so maybe they are marking up the GM parts enough to have a reason not to tell? I just want caliper brackets and backing plates, and I can go to the parts store and buy the rest myself brand new without overpaying for stock parts, plus shipping for those parts!
Capev86, Look up Bowtie Overdrives, in Victorville, CA. I bought an OD trans from them......best money Ive spent so far for my truck!

Re: HO72 rearend rebuild
 

The parts are out there and it cause a brain tumor!
There is an outfit in California that I purchased brand new drums for my HO-52. I'm at work right now, (cant recall who) but could look up the paperwork when home if anyone needs the contact information. They were Pricy, but was nice to have the rear end back factory. All the brake components I got from an outfit in Mass that specializes in brakes for the old stuff. I got brand new OEM parts and I'll tell ya..for manual drum brakes they act like power brakes!

Where theres a will theres a way!

Re: HO72 rearend rebuild
 

If you don't mind posting that info, it would be nice to have -- just in case. My drums are OK for now, but there's not enough metal left if they ever need to be turned.