New agenda: Front Calipers

Well, Rambini is experiencing a dragging LF brake. Gets real hot on a 2 mile run. Not good. A 1989 Ram50, 2.6l, 4x4 short box. 230k miles.
Found caliper guides good and clear. Mr. Piston not so much. Around 50K since reman cal's, pads & such.
Any thoughts on reman units, NAPA carries them and extras?
Brake lines look pretty good, but what comes apart after 30+ years?
Please share feelings and fun stuff before I leave the dock.
I treasure the knowledge and hard earned experience shared here.
Thanks, Tlunny

Go and grab the calipers off a 94-2000 Montero. They bolt up and are dual piston vs single. The later Sports would work up to 2000 as well. I think in 2001 the sports switch to the "Big brakes" (larger rotors but same calipers). Can get those as well, but you would need to run 16" wheels to clear. Ive ran both and either is a great upgrade to stock.

Also, no need to upgrade your master cylinder either. Stock is sufficient.

Take a look at your load sensing proportion valve in the rear above the axle

What should I be looking for?? My LF piston is very hard to retract with a bar. When brakes are applied, it stays dragging, a tap on the caliper will free it up. Doesn't feel like the pressure is being trapped.
What else do I look for. Would I expect to show pressure at line or bleeder? I have calipers coming.

Ok so this is what I'd be looking for. Take the caliper off the mounting bracket and examine the slide pins. Look for scuffs/discolouration or obvious signs of wear. This will indicate if the slide pins or the bolts holding them in were loose or has been mechanically damaged/bent. Check the brake pad shims for wear, bending or gouging/scratches. Gently remove the rubber boots from the caliper, clean and flush them out thoroughly with degreaser and inspect for splits or deterioration. If you've made it this far and not seen any damage, buy a spray can of tire shine and a tube of marine grease. Hose the rubber boots down with tire shine and knead it into the rubber. This will rejuvenate the rubber and prolong their life (and makes them look like new). Install the boots into the brake caliper and apply the marine grease to reinstall the caliper. If your brake pad shims are gouged, replace them. Otherwise you can clean and polish them with fine grade steel wool and a metal polishing compound and paper towel. You can use fine grade steel wool and polishing compound to remove minor surface rust and crud from brake pistons as well but if they have pitting or gouges from being in contact with the caliper inner wall they need to be replaced.

Thanks Geezer. This problem is LF only. Slide pins were lured and pristine, no binding or corrosion. Piston boot looked good, didn't remove.
Piston was very tough to retract, pads were floating and free. After brakes are applied and released LF is almost unable to turn wheel by hand. One good thump with a soft mallet on piston side of caliper and it rolls freely. I just feels to me I have crud and corrosion between piston and bore, maybe failing seal? As crvtec90 asked on load sensing, can it trap pressure to an individual brake? My RF side works perfect.

I wouldn't dismiss the load proportioning valve but in theory, a whack with a mallet shouldn't cause a pressure release caused by a component at the other end of the truck. I think you need to blow the piston out of the caliper and give the inner reservoir and walls etc a good cleaning. I would also consider replacing the rubber brake lines. They can come apart internally as well + years of service can weaken them to the point where they expand and drop pressure. I hate messing with brakes. They can be temperamental and they are kind of important to get right lol.

Quote:

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Originally Posted by geezer101

I would also consider replacing the rubber brake lines. They can come apart internally as well + years of service can weaken them to the point where they expand and drop pressure.

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+1 to that. Old hoses can internally collapse, swell, or otherwise get blocked, which can effectively act as a sort of check valve, causing the caliper they feed to hold pressure after the pedal is released.

FWIW, user B-Line here sells braided-stainless jacketed brake line sets tailor-made for our trucks -- more info and pics:

http://www.mightyram50.net/vbulletin...our-Mighty-RAM!

http://www.mightyram50.net/vbulletin...ed-Brake-Lines

I picked up my Braided Stainless Steel set from them several years back now. Top notch quality stainless brake lines.

Teflon sleeved braided brake hoses are an awesome addition to new brakes. Anything that can improve positive brake pedal feel is worth the investment (plus I think you'll be struggling to not only find OEM style brake hoses, but the prices won't be much different to something that is equal to a performance aftermarket part)

Thanks everyone. If I'm in need, I'll "B-Line" to the obvious supplier of quality brake hoses.
Guess I'll keep the fuel line and worm clamps for ex wives and enemies.....

Brakes working OK now ? My 1986 truck front brake have begun to noticably grab when first moving making a vibrating noise... Dang

Well, just got my reman calipers and it will be next week before I can attack the unit.
Rambini is generally a town runner and ours is about a mile end to end. Had a severe pull to left after a 2mi 50mph run. LF was cooking. Busy so did a another test and jacked up finding noticeable drag. Piston is hanging, will advise what I find. Thanks for the interest, hope your problem is minimal.

Oh sorry I did not mean that the lspv would cause that particular issue. I just mean take a look at it . Its old . Mine was leaking. I had recently come to find my brakes were in need of repairs and never really even noticed any stopping issues.

Also lift up the rubber boots on the rear wheel cylinders to look for fluid leaks and or corrosion.

Look at the master cylinder where it meets the booster . Any evidence of fluid leaks and or corrosion?

If your hoses are original I would recommend replacing. Ive seen many people burn up brand new brake rotors and pads due to bad hoses/

Good luck with replacement parts. Its pretty much a throw of the dice these days in my humble opinion . Quality has gone out the way to make room for profit but thats just me complaining

Rambini ~ where did you find rebuilt calipers ?

It appears that all is well! My awesome NAPA parts man found my reman calipers from Federated parts. NAPA listed them but none available.
I got floating calipers with brackets not loaded with pads. When I went to loosen brake lines from calipers I pushed as hard as I dared with a quality 6 point tubing wrench and then borrowed a 10mm Snap on and it felt like a different nut. Broke loose just fine. I have a set of fractional sizes but had no metrics. They're amazing. Bled out great and no more LF pad drag.
Thank you everyone for your help and comments. This group rocks!
Thanks again!

Excellent outcome :thumbup:And invest in a set of metric sockets and wrenches - you're gonna need them.

Rambini thanks for the update & parts source info ~ glad you can enjoy your ride again :) yep folks here are pretty awesome !!

Oh I've got everything metric except the tubing wrenches. 40+yrs of mechanic on a little bit of everything. Just never worked on anything with metric tubing nuts.
And another Snap on plug....if your making your living or have to make it work, their flank drive tubing wrenches rock.
Thanks again. Lunny