for some reason when i stop the rear tires keep on spinning...this usually happens on snow, sand, wet pavement, and sometimes dry street. Of course this unables me to stop alot sooner than I have to sometimes so I just maintain a "safe" distance from other drivers..What the heck could be wrong with the rear drums? I just bought the car...Think they need to be replaced? and also the parking brake does not work, I tested it by driving 5 mph and i ripped it up and the car just kept driving the same speed...any suggestions? Sounds dumb but help me

 

A bad combination valve. Do this mod and your drum brakes should work again.

Important note: Permatex sells thread sealant in small tubes (look just like their threadlock tubes) that is impervious to Hydraulic fluid- this is better that teflon tape.
Mod thread- https://www.thirdgen.org/techbb2/sho...ight=%2Amod%2A

This is a qiuck $5 dollar mod that will give you rear brakes again but raises your rear proportion slightly. Or you can spend $100 on a new Disc/Drum combination valve (J50) for 82-early 89 cars.
Part # is 14089495

 

I wanted to add that I did this mod awhile back when I also changed my car to disc rear. The brakes worked great for several months- however, the front brakes finally started to fade in pressure as well (backs remained fine). You can not do this mod to the front side of the valve! At this point I switched to the 1LE combination valve (J65) that came on the performance package cars with 4-wheel disc / Early '89 (1st design) for the 82-early 89 cars will bolt right up to your line fittings. Part# 14089496

 

The drum brakes might need to be rebuilt, too. I had a bent lever in mine; it wasn't rubbing against the adjuster wheel. I just bent it back with pliers! If you just got the car, you might as well give the brakes a once-over. Just remember not to press the brake pedal when the rear drums are off- the drum brakes will fly apart, and might hit people/cars/birds that are nearby.

 

Call Dal...my prop (IE combo valve, P/N 14089496) for my 1LE system was $55 shipped.

From GMPD:

GM PART # 14089496
DESCRIPTION: VALVE ASM
PACK QTY: 1
CORE CHARGE: $0.00
GM LIST: $97.09
OUR PRICE: $48.55

Ed

 

Hey AGOOD2.8, how did your car perform with the 1LE combination valve? I am now thinking of doing that also.

 

bttt.

 

Sorry I missed this. The 1LE combo valve works well- fronts are locking just alittle too soon for my liking when hard on it- but it could be a result of worn tires. I will need a new set within a month or two- I'm locking the inside front wheel easier than before with just the J50 valve w/ the Mod (plug) performed to it. Once I get the new rubber I'll have to do a little lightweight track time to get it dialed right, I am still iffy with the rear bar changes and combo valve changes going on at once.

P.s. I don't often drive this car more than once or twice a week for a quick trip here or there. Sometimes when I jump on it hard in a corner I can be alittle aggresive from lack of knowing the cars feel. I drive a built lowered chev truck all week and its a big change jumping into this little car for a quick 5 min. jont to the store or such.

Edit: we've also had alot of rain here in So. Cal the last few weeks and the roads are slick- haven't had the traction or ability in driving time to get the tires hot enough for good predictable testing. Stopping straight is fine and balanced well for normal to hard everyday street use, but thats not a concern of mine- I want it to do things for me setting into corners.

 

86, also check for a leaking wheel cylinder. If it won't hold pressure the wheel won't stop.

Ed

 

I have a 1987 GTA with stock 4 wheel discs and when I hit the brakes the fronts work to a point and eventhough I push harder it does not make any difference. I have bled and bled the brakes and it has not fixed it. I think that the rears are not even working, I am convinced that I need to get the 1LE prop valve or do the valve mod. Am I correct??

 

For the most part I would say yes- even if this isn't the exact problem- the 1LE J65 (#14089496) combo vlve certainly is an improvement over the J50 combo valve you presently have. Also check for bad lines or blockage. As long as you are bleeding them and are getting a decent flow of fluid then you don't have blockage. If you have stock soft brake lines(rubber) you may want to consider upgrading to braided lines(You may already have these?)

 

If your park brake is hooked up correctly and the cables etc are all there than it sounds to me your drum adjusters are frozen. These are sometimes called starwheels. They are located between the shoes on the bottom, and if you remove them free them up put anti-sieze on the treads they will work fine and keep the shoes close to the drum. When you re-install the drums there should be a slight drag when you turn them. This is a real common problem on GM rear drums. Please note that the adjusters have to stay on their respective sides because one side is left hand thread and the other is right hand thread.

 

No I have the stock rubber lines, and I also have 4 wheel disc brakes, not drums, but thanks anyway. I have not touched the rear calipers as of yet, as soon as I get it out of storage I will check them out for any binding.

 

Aaron, since you said you haven't touched the calipers yet, I take it you haven't installed the recall kit either? Your calipers probably aren't working right and therefore neither is your e-brake mechanism. Have you looked into installing the recall kit first? This may cure you of your problems. I would look into this before I did anything to the prop valve.

Search for "caliper recall kit" or something with "recall" in the search.

HTH...Ed

 

is the 1le valve the same as a 89-92 4 wheel disc valve.Or the question is will a 92 4 wheel disc vale work good with a 1le setup

 

I was not aware of the recall kit, I do not frequent this fourm. I will try that when I get it out and see if it helps.

 

i am still unclear if it's there are any differences in doing the mod to the original PV on a 92 with rear drums? seems like most of you have disc rear.

 

You mean the spring mod? I understand the concept but I wouldn't do it. Too much of a chance to make a leak in the system.

Ed

 

right, but i believe you can just replace the plug with a 3/8" NPT pipe plug instead of tappping or welding it. will removing the guts of the PV work well on rear drum brake cars too? or should i just get an adjustable PV? seems like if the wheel cylinders were properly sized (bore) then there would be no point in having a PV at all? thanks.

 

IMO, if the brakes are working as designed with good working components there's no need for it. My RS has the J50 disc/drums and stops fine. My 1LE Iroc stops even better. I DO understand and support installing a Wilwood-style adjustable valve in there. This valve would probably work great with the prop valve mod since you will have total control of the pressure adjustment.

Ed

 

will your rear drum brakes lock up on wet pavement? mine won't. they appear to be working, but just not enough.