F&R drum brakes, stopping power?

hey all

question of the day.

hows the stopping power when you have drums front and rear. i think they are both 11"


i was going to use the discs from the donor jeep I'm getting, but i already have a buyer for everything i don't use, and he wanted it to be able to roll...so I'm leaving the brakes and knuckles for the sake of keeping the sale easy.

CJ6, on 33" (tires most likely)...right now its on 31's though. it has power brakes, not sure if power brakes are factory or if someone added it later.....the brakes will get a complete rebuild...so hopefully everything will work as good as originally intended.



i figure it will do some time on the street occasionally.....more time on the trail.....but will be trailered to and from when it does.

will it be OK with the drums? or should i really start looking for the axle parts needed for the conversion.


any advice is appreciated

thanks

 

I never had much of a problem stopping with my drums except when they got wet they seemed kind of dangerous, this is the reason I changed mine to disk. I like to cross the creeks and play in the puddles when weeling and winter has a lot of standing water on the roads.

 

oh yea..... when keeping the drums i plan to have them drilled.....i've read a few articles in various mags and websites that says it helps A LOT in water and with fade in general!

thoughts on that would be super duper too

 

Check the Tech Library tab at the top of the page. Then try a search. Tons of info. I'm considering the drum drill myself. Folks seem pretty happy with the results...

 

The original 11" drums on my CJ6 with a V8 stop it and 33's fine on the street.
Mine is going to stay original except the lift and tires but if I was going to build a trail rig out of it I would swap over to discs for the stopping power. The 3b I am building is all discs.
I have gone from 4 wheel drums to 4 wheel discs before on the Mustang and there is a huge difference!

 

easiest and least expensive bolt on solution is 11" drums. My 2A has 11" front drums and the itty bitty stocker drums on the rear. Stops 33's no problem -- all 4 with 11's must be awesome.

4 wheel discs are pretty cool and perform great. It is just a big project and $$$ eater. You have to change all your lines as discs use smaller diameter.

 

right, i've seen the tech library articles....

i did a search and didnt find too much


i'm sorta looking for a first hand account from someone with before and after experience

 

with 11" power drum brakes, it should stop on a dime, if all adjusted properly and all in good working order.
and yes, the power booster could be factory, an option at that time.

 

I think they are fine, if in good condition. My previous CJs ('73 and '75) both had factory power brakes, and yes, they would stop on a dime. The main drawback on the trail is the fairly light pedal ... neck-snapping stops can result from braking over big bumps.

Today, you may have a hard time finding an exact replacement booster. I looked a while back, and my only option would be sending my core to a reman service.

If you have factory power brakes, I could use close-up pictures of the firewall mounting and the booster.

A '75 will have finned drums, which would make drilling more difficult. The main reason you might want to upgrade to disks would be 1) less fade, 2) self-wiping (water), and 3) less maintenance. Drums will require more frequent renewal, and are more complicated.

 

I'm pretty sure lynn did this swap.

He should chime in any minute now...

 

I almost cracked my windshield because the passenger in my 74 CJ-5 didn't believe me when I said the non-power drum brakes stopped on a dime. The fool wasn't wearing a seatbelt and we were only going about 10mph, but I slammed on the brakes and he kissed the windshield pretty hard. He never questioned its braking ability after that though. But get them wet and you might as well have Flinstone's brakes because they are totally useless until they dry out.

 

Personally I would swap out the drums. Yes they will stop but keeping them in adjustment can be a full time job IMO . I would get them adjusted and then they would stop straight about 3 or 4 times then it would be anyones guess which direction it was going to pull. With the discs hands off much more stopping power and water isn't an issue. There IS a reason they changed from drums to disc systems.

 

Comment on adjustment - these are supposed to be self-adjusting brakes. The Bendix self adjusters work fine if there are no grooves worn into the backing plates, if you use new hardware when renewing them, and if the drums haven't been turned to their maximum diameter. You also have to be careful to put the components on right - the adjusters have a right and left side, and if you put them on backwards or reverse the sides, they will not work (in fact, they will loosen as you drive).

When you renew the brakes, put everything together and test that the adjusters on every wheel tighten when you pull on the cable (squeeze the cable toward the shoe with your thumb). The pawl will climb the star wheel. When you release, the brakes should tighten (ie the adjuster lengthens). Use a brake caliper to preset the distance between the shoes and the drum (that's the best method ... but you need to buy the tool). Then when it's all together, back up and jam on the brakes a few times to tighen the adjusters and even out all four sets.

hth!

 

can i use non finned drums with my factory 75 11" brakes? any difference in size, or is it just a matter of finned and non-finned?

I'll likely farm it out to a machine shop....so fins or no fins shouldn't make much of a difference if they are worth anything. my drill press isn't big enough to do it myself....not sure i trust myself either.


periodic adjustment shouldnt be a big deal......i dont tend to drive my jeeps all that often, only nice days and maybe some roads around where i go offroading (sometimes we park the trailers at the campsite and drive the jeeps to wherever we are wheel'n)

thanks...appreciate the help all......i'm leaning pretty strong to the drilled drums instead of discs now....

now if only we could make changing drum brake parts as easy as discs

 

Maybe I'm putting too fine a point on this, but...
If your 11" Bendix brakes need periodic adjustment, something's broken.

 

well thats good to know too!

i have yet to ever drive this jeep....so i dont know whats normal for these brakes.

it was dead when it got dropped off in January....and the only time its moved was when i pushed it back further into my garage so the 2a could fit in front of it. its current "brakes" consist of chucks of wood pushed in front and behind the tires

 

I have powered brakes. I did the Chevy disc swap to my front axle. I repaired the stock 10" drums on my rear. Unbelievable difference; like a whole new vehicle. I will never go back to drums. I know that the 11" can perform well, especially with the drilled drums, but for me the discs were a better fit with my driving, performance, and maintenance needs. My main complaint with the non-drilled drums was not with getting them wet and losing performance, it was just when only one side would get wet and cause random lane changes when in traffic. My discs have yet to do this.