1970 k20 Drum Brakes, info req'd.

[Former member Yoder213]

So I couldn't find any older threads on this. I know there's a lot about brakes on here. but, still couldn't find a satisfactory answer.

I've got the 70 k20 and from what I found they put an oddball sized brake drums on these suckers. 12 x 2? I've heard 12 x 2 1/4, and a couple other things that have had me doubting, and part shops don't list em.

Brake shop says I'm 1/4 past legal, a year ago. and wanted me to switch out for a 92 suburban diff set, supposed to perfectly bolt in, no hassle. for the same price as a disc conversion kit (don't know if they had a rear kit with it)

A couple older mechanics said if I loved the truck, keep it original, So that is what I'm looking for. new drums.

now LMC has them for 250 a drum. OUCH.
tuckers, and one other site says they have them for 60 a drum, or about 130 a pair, but I don't know if I should have faith they are the right part.

tuckers sent me the specs on their drum, funny thing is was in metric, kinda raises another flag for me, and I am wondering if I can get some specs for THE drum that goes on the truck, or any other advice on finding these drums. I found a pair off an 81 at pick n pull, but I haven't found out if they fit, seeing as tearing apart the rear end requires some hours and focus, I want to know I can do the job when I start.

would it be worth the pain to order and see if they work, or keep hunting?
what would be pros and cons to going to the burb' diffs?
Thank you
Jason

[lolife99]

Can anyone help?

[Former member Yoder213]

another interesting thing is there is almost a 5lb difference between the two drums.

[jeffahart]

I am in a similar dilemma. I have a K20 with Dana 44 open Knuckle in the front. I need to do a brake job but have been holding off because I would rather convert to disc. I bled my brakes when I got the truck and they have been OK since, only OK, which is not good! But I hesitate to start a job I am not prepared to replace all parts on; which is not huge money but enough to make me hold off on my decision.

I have decided to go with disc up front. Why, because, IMO, keeping front axle original is not worth it on a 70 K20(unless it's a low mile super clean one) as far a brakes are concerned. The 71 had Disc. Plus everyone assumes disc on the 70 anyway.

That said, the decision to go with discs means I've committed to a front axle swap. If you do research, this is what everyone with experience says to do. If you do not you will need someone to machine rotors to fit and your brake system will start becoming an aardvark of components. Which is OK if you are into that. I am not.

Now the decision will become Dana 44 or 60. I am leaning toward the 60.

Then there is the rear brakes. I have been hording two new wheel cylinders for the eaton. I hear they are becoming hard to get.

So my plan.

1 - Swap in a disc brake axle (44 or 60) and then I can put on big winch bumper and tires and not worry about strength. I may never, but as long as I have my hands on it I want to put in best axle I can. I believe the Dana 60 fits the bill. And you can read on this forum(and many others) and see it is a straight bolt in. I have this slated for this year.

2 - I will continue to research what rear axle I want and how to resolve parking brake. I am leaning toward keeping the eaton HO52 that is in it, it has the original locker and I like the axle.

3 - My plan is to continue on toward the rear. After front axle I will do the 205 then the sm465 then by that time I will have made a decision on the rear axle. Although I am leaning toward keeping the eaton as is.

I really feel like the 1970 K20 drum axle is a redo since they have no disc brakes.

In the old days I had no issue with drums, it's what everyone had. Now I have a choice and in later life have learned to really put off a drum brake job. I NASCAR pit crew when it comes to Disc brakes, But I always seem to fight with drum components.

I think if you put a new dana 44 disc brake axle in your truck it would never hurt your resale value, but I think having drums up front could make someone shy away from the purchase.

[Former member Yoder213]

Thank you jeffahart.
I'm a n00b, but not so much to trust everyone off the street 100%

[jeffahart]

Originally Posted by Yoder213

Thank you jeffahart.
I'm a n00b, but not so much to trust everyone off the street 100%

Even reputable shops will give trouble. I called three reputable offroad shops around me to rebuild a disc dana 44.

first two told me just to convert it would be no problem. They said they would work up price and call me back. Never called me back. I guess they called around and decided the conversion was not in fact that straight forward.

The third shop knew it would be easier to swap(this is a well known off road shop in Burbank Ca). I asked how much for a axle rebuild and install. They said they would call back. That was last week and no phone call back. Business must be good.

Looks like I will be doing it myself.

Also, here's a good one for you.

I took my truck to a radiator shop after I got it to have the radiator flushed. I drove there with my son.

The truck was making the metal clacking. When we got to the shop I was talking to my son about it, as we were trying to figure it out. The radiator guy interjected and said his brother was a tranny man. I said nothing. Later when I came to pick up the truck the guys brother was there and he said the the transmission was shot and needed a rebuild. I said "Thanks, I do myself tomorrow". Paid for the radiator flush.

The next day we figured out the clacking noise. Orange 76 ball on the spring antenna was catching wind and causing the antenna to clack against the drip rail on the top of the cab. I took the orange 76 ball off the antenna and now the tranny is fine.

Never pay to get anything fixed you don't know for sure is the problem.

[Former member Yoder213]

I agree, the shop I took it to had done a free brake inspection, not knowing they would have to deal with pulling the axles they spent 4 hours inspecting my brakes. The PO was mad (gf's dad) that I let them under the truck and wanted to test drive it immediately to make sure they didn't swipe and locker parts, and was troubled they put washers in backwards.

Never went back, figured they wanted my axles. wonder if I could get another free brake inspection and get the same response.

sounds like an axle swap on the front, there's a couple on craigslist here for 150.

again thanks to all!

[Former member Yoder213]

123.66036 is CENTRIC's part number,
but they don't guarantee its correct, one online store has over 35 of them.
and one site lists them as a suburban part
and one site says they are for mid 50's trucks.

the more I dive the more bottomless it looks

[tj_1970_k20]

I am in the same situation. I've got a 1970 K20 pickup with a Dana 44 front axle and drum brakes. My drums are 12.120" which is 0.30" over the maximum diameter. I am trying to get some drums made by DuraBrake. I sent them a drawing and I'm waiting to hear about cost. They told me minimum order is 8 pieces. I want 4 for myself, so I'd be looking to sell the rest. If any of you want in on the deal let me know.

I exchanged emails with Centric and they don't have the drums and don't do custom jobs.

My drums were made by Budd with casting number 95478.

[tj_1970_k20]

I've got a quote from a brake manufacturer for $260 per drum. Minimum order is 8 drums so I'm looking for some other buyers to go in on the deal.

I called LMC Truck and they said they don't have front drums for the 1970 K20 pickup.