does anyone make a rear disc brake conversion for a 61?im starting all the chassis work this weekend and so far i havent found any for it yet

 

If your 61's a 1/2 ton you'd have a 9 inch rear and I know there's a ton of disc setups for that axle. Try Summit Racing for one.

If it's an F250 please disregard .....

 

Classic Performance Products lists a rear disc brake kit however,theres a note that says will not work with rear ends.I'm going over there tomorrow for some parts I'll ask about it.

 

I did some extensive reading through this forum when I decided to put discs on the front of my 63. I recall a discussion about rear discs, and if I remember correctly,the final agreement was that rear discs were more trouble and cost than they were worth. I didn't research rear discs much, but, I don't recall any kits mentioned. You could get a newer 9" axle with discs already on it, but newer axles are wider.

Doing a search in this forum might be an idea.

 

tons of kits made for them but in the end you notice not much difference in stopping power. sometimes less because the original system is not made to for disc brakes. it can not sustain the pressure loss so you get a spongy pedal.

 

I always try to shoot this idea down. It's an unnecessary waste of money, unless you are building a show truck and want the bling or are building something capable of setting a land speed record.

Rear discs will provide much greater stopping power on the axle with no weight on it. Which means it will want to lock up sooner, putting your truck into a spin. This is why pickups stuck with rear drums until the advent of ABS.

Unlike a car, all the braking on a truck (empty) is really done by the front brakes. This is where you should place your efforts. A front disc conversion is more than adequate to provide safe, controlled braking.

 

you would be better off using 1 ton booster and mc to increase brake power rather than do discs out back. up front yes but not in back.

 

Installed properly, rear disc systems work very well. Wilwood makes a nice set-up.
I would re-plumb the entire vehicle, making sure to use a disc/disc master cylinder.
The four wheel disc master re design delivers the extra needed volume and pressure to the rear allowing your rear disc brakes to function properly. If you attempt to use a disc/drum master on a four wheel disc system you will get poor rear brake function and experience a spongy brake pedal with a long pedal travel.
A residual valve is not necessary on a disc/disc system, when the master is firewall mounted.

 

Unlike the front, adding better brakes to the rear won't give you more stopping power. If you add bigger brakes to the front, you adjust the brake bias, or brake ballance so that you maintain the propper split. rear drums on these trucks can handle much more than they are required, so if you increas your braking ability by 20% on the front, you can still balance the system by increasing pressure to the rear. It doesn't work in reverse. your front brakes opperate at 100%, so can't increas them to match new, better rear brakes.

on a car, you normaly have a 60/40 split on front and rear brakes. the rear doing 40% of the job. But on a truck, that is more variable. Depending on bed leingth and type, the split can be from 60/40 to 80/20, but is usualy in the 70/30 range, with no load.

on normal, dry days, a drum will stop nearly as well as a disc. Its in hard, extended use and wet enough conditions to get water into the drum that the Disc is truely better. Unless you ride the breaks down mountians, or drive your truck like a rally racer, you aren't likely to get the breaks hot enough to have a problem with brake fade on the rear.

The other problem with Disc is there tendancy to lock up. balanced on a car, this is rarely a problem, but if you balance them for an empty truck, they will lock with a load in the bed. balance them for having a 500 pound load in the bed, they won't work empty, and lock at 1000 pounds.(weights for example only) The problem is the linear progression of disc versus the non linear progression of drums. to simplify, if you press on the pedal of a disc brake system, the brakes will lock at the same point each time. With a drum, the more weight on the brakes, the higher the point at where they will lock, so in effect, they can adapt to a load in the bed. This is partly why big rigs still use drums. DDAVIDV had it right, Disc didn't work for trucks untill ABS became common.

 

This was very informative, thank you all for some good reading here. I think I'll go with a power drum setup and save myself a ton of extra headaches and $$$

 

yes my truck is a half ton with a 9 inch rear end.yes its gonna be a showtruck.so the weight problem is no big deal im gonna smooth the bedfloor so nothin will ever be put back there.the stock pedal issue is no biggie bc im goin to lokar and getting some pedals from them. yes im also redoing the entire brake system.im goin with mustang 2 ifs in front.the reason why i dont like drumns is bc i have them on my ranger and everytime it rains they catch really hard,my dad has 4 wheel disc on his silverado and i can tell a big difference in driving my ranger and his truck but his does have a trailer behind it all the time maybe thats the difference.after driving mine everyday and then driving his i though it would be best if i could do that conversion since its gonna be a show truck.thats the main reason i was wanting 4 wheel disc plus itll look better.yea minishtr id appreciate any info you can give me on those setups.thank you everyone ive really learned alot.

 

your dad's silverado will have ABS, so its an apples and oranges comparison.

But a show truck is a whole other thing! http://www.blackbirdscustomtrucks.com/index8.html#59sb this may be what you need.

If you are going to the Mustang2 front end, you might consider the ford 8.8 rear end instead of retro fitting brakes onto the 9 incher. A late model axle from an Explorer comes stock with 3.73 gears and disc brakes. Most have positraction, too. $200 from a junkyard, so way cheaper than converting your 9 inch. the 8.8 is a 29 spline axle, so same axle striength as the 9 inchers 29 splines.

 

thanks 66 beater ill check on that.i have a friend who could hook me up with that axle,i looked at that website and it its kinda pricey.

 

Ok so I should remove the rear discs (already on the truck when I bought it) and put on some drums?

I never paid much attention to the brake system as I am going to have it done professionally (I hate brake work).

The truck hasn't moved in 3 years and probably won't move for another year depending on income so I have time.

When it does move it will be a daily driver and will occassionally be hauling stuff.