Convert 70 to 72 Disc brakes

[Olive1970]

I think I have a good idea for what needs to be changed in the swap as far as suspension parts.

Use upper and lower control arms and spindles.
Use calipers and hoses.

Now, what can be done for using my 1970 steering components on the 1972 spindle?
I will be purchasing 6 lug rotors through ECE or CPP because I want to keep the 6 lug for the original rallye wheels and cost of new wheels with 5 lug.

Is there anything else I am overlooking?

Thank You!

[seaflea]

Not sure if this helps, but its what I have been using as a guide for my 69 disk brake swap
http://67-72chevytrucks.com/vboard/s...68&postcount=4

[Olive1970]

Originally Posted by seaflea

Not sure if this helps, but its what I have been using as a guide for my 69 disk brake swap
http://67-72chevytrucks.com/vboard/s...68&postcount=4

That is very helpful for what I am dreamin up. Thanks!

Does anyone have a part number or access to the said thread converter to change the inner and outer tie rod ends between 70 and 72?

[~Whitey~]

I changed my drag link on my 69 to a 71-72 style when I did my disc brake conversion, and then just bought 71-72 inners and put it all together, already had to buy the 72 outers since I had the 72 spindles. Only problem is that the drag link is not something you can buy from a parts store, you'll have to find one from a friend or parts truck. If you want to keep your 70 drag link, you can, but will just need an adapter sleeve between the 72 outers and your 70 inners.

[Olive1970]

Originally Posted by 69swb

I changed my drag link on my 69 to a 71-72 style when I did my disc brake conversion, and then just bought 71-72 inners and put it all together, already had to buy the 72 outers since I had the 72 spindles. Only problem is that the drag link is not something you can buy from a parts store, you'll have to find one from a friend or parts truck. If you want to keep your 70 drag link, you can, but will just need an adapter sleeve between the 72 outers and your 70 inners.

That works too, I will have a parts truck to pull it off of. I just replaced all the parts on the 70 last year, so I was trying to save what I have new already

[lolife99]

I really, really, really, really, really, suggest using new converion spindles for 63-70 trucks.
Then you can use your stock '70 steering components.

Otherwise, you have to buy the $50-$60 tie rod adapters, and 63-70 outer tie rods, (to use in the inner location), and 71-72 outer tie rods.

A 71-72 centerlink would allow you to use 71-72 inner and outers with a stock tie rod sleeve,... but you have to find a nice used one.
These are not sold new anymore.

The conversion spindles are as cheap as $229.
And ECE 6-lug rotors will work fine.

I assume you have wheels that will work with the 6-lug rotors?

[Olive1970]

Originally Posted by lolife99

I really, really, really, really, really, suggest using new converion spindles for 63-70 trucks.
Then you can use your stock '70 steering components.

Otherwise, you have to buy the $50-$60 tie rod adapters, and 63-70 outer tie rods, (to use in the inner location), and 71-72 outer tie rods.

A 71-72 centerlink would allow you to use 71-72 inner and outers with a stock tie rod sleeve,... but you have to find a nice used one.
These are not sold new anymore.

The conversion spindles are as cheap as $229.
And ECE 6-lug rotors will work fine.

I assume you have wheels that will work with the 6-lug rotors?

If using the new conversion spindles for my 70 would be the best route to go, then I will do that instead of using the 72 spindles probably. I just figured that since I had all of the 72 parts I should use them.

From the sounds of it, I would be just using the calipers and hoses then?

The wheels I have will work with the 6 lug rotors, at least according to pictures that are on some of the vendor websites.

[lolife99]

If you have ALL of the 72 parts then use them.
You won't need conversion tie rod sleeves.

Just assemble your truck with ALL 71-72 parts.
Just my opinion,... I would buy new hoses and calipers.

Are you using drop spindles or standard spindles?

[~Whitey~]

Originally Posted by Olive1970

I just figured that since I had all of the 72 parts I should use them.

Sounds like you have almost everything you need either way you go, just a choice whether to buy aftermarket spindles or new tie rods/sleeves, which would be considerable cheaper I believe.

[Olive1970]

Originally Posted by lolife99

If you have ALL of the 72 parts then use them.
You won't need conversion tie rod sleeves.

Just assemble your truck with ALL 71-72 parts.
Just my opinion,... I would buy new hoses and calipers.

Are you using drop spindles or standard spindles?

I do have the complete front end for the 71-72, but im sure some of the old components are shot. The truck has been sitting for 10 years.

With that being said, definitely wise to replace the hoses and calipers.

I do have the standard spindles, but was thinking about using drop spindles for the swap.

[Olive1970]

Would I have to change my MC and prop valve for going to front disc? I currently have power drums on the 70.

It seems some vendors say yes, others make no mention of it.

[MARKDTN]

Originally Posted by Olive1970

Would I have to change my MC and prop valve for going to front disc? I currently have power drums on the 70.

It seems some vendors say yes, others make no mention of it.

Yes, a disc brake takes more volume than a drum.

[~Whitey~]

Originally Posted by Olive1970

Would I have to change my MC and prop valve for going to front disc? I currently have power drums on the 70.

It seems some vendors say yes, others make no mention of it.

Yes. You will need a disc/drum master cylinder and prop valve.

[Olive1970]

Originally Posted by 69swb

Yes. You will need a disc/drum master cylinder and prop valve.

Do you know if a manual brake 72 prop valve can be used with a power 72 master cylinder?

[First c10]

When I updated my MC i updated to a 72 MC but connected it to my original 70 brakelines and prop valve. So when i update to disc i only need to install new lines to each caliper and a Disc/Drum Prop valve.
good luck and keep us updated!!!

[lolife99]

Originally Posted by Olive1970

Do you know if a manual brake 72 prop valve can be used with a power 72 master cylinder?

yes.

[~Whitey~]

Originally Posted by Olive1970

Do you know if a manual brake 72 prop valve can be used with a power 72 master cylinder?

Originally Posted by lolife99

yes.

ditto

[lolife99]

Originally Posted by Olive1970

I do have the standard spindles, but was thinking about using drop spindles for the swap.

This is a point I try to make all the time.
You have a complete 71-72 front end.
Now you are buying 71-72 drop spindles.

So you will be using what old parts off the 71-72 front end?
1) centerlink
2) dust shields
3) tie rod sleeves (maybe)
Everything else will be new.

SO if you bought 63-70 drop spindles,... you would use the following old parts off the 70 front end:
1) centerlink
2) tie rod sleeves (maybe)
Everything else will be new.

So was there really a need to get the 71-72 front end???
No. Not any more.
(I know you already had yours)

[Olive1970]

Originally Posted by lolife99

This is a point I try to make al the time.
You have a complete 71-72 front end.
Now you are buying 71-72 drop spindles.

So you will be using what old parts off the 71-72 front end?
1) centerlink
2) dust shields
3) tie rod sleeves (maybe)
Everything else will be new.

SO if you bought 63-70 drop spindles,... you would use the following old parts off the 70 front end:
1) centerlink
2) tie rod sleeves (maybe)
Everything else will be new.

So was there really a need to get the 71-72 front end???
No. Not any more.
(I know you already had yours)

This is very valid point, almost better to stick with the bones on the 70 since it already has all new parts and do the swap for a 70. Luckily, this is something that is still on the 72 but have considered using it. I might be better off selling it seperate or with the frame once I have stripped the other body parts.

[First c10]

Question ? if you do change to newer components do you have to change pitman arms? like 67-68 truck to 69-70 or 71-72 or 73-81 pitman arm?

[lolife99]

Pitman arms usually have to match the steering box (manual or power),... and centerlink.
I have found them broke down in these groups.
*60-66 Manual
*60-66 P/S
*67-72 Manual
*67-87 P/S (Specify Year When Ordering)

[First c10]

Soooo if you had a 70 with factory PS and changed the front end to 79 the 70 pitman arm can be used as long as it is good? even though the centerlink is 79?
sorry didnt mean to hijack the thread.

[lolife99]

Originally Posted by First c10

Soooo if you had a 70 with factory PS and changed the front end to 79 the 70 pitman arm can be used as long as it is good? even though the centerlink is 79?
sorry didnt mean to hijack the thread.

I believe your '70 p/s pitman arm would work with your '79 centerlink.
Its all a matter of reseach.
I don't know every answer,... I try to use my books and Google to help find answers.

The reason I say yes,... to your question,... I once installed a '76 p/s box on a '70 truck.

You can "what if" stuff forever,...
If you have the box,... it's all a matter of trying it.
Thats how we did it back in the 80's,... when no other parts or info was available.

[First c10]

I appreciate you helping with anything you can. I dont think you would steer me in the wrong direction (Steer Get it?) I know i know!!!
Thanks
I will be try this soon!!