thunder85

iTrader: (1)

Good Morning,

I have an 88 gta with the common "back brakes don't work" issue(4 wheel disk brakes). My ebrake works, so per the previous threads on the subject my proportioning valve has failed. It is recommended to obtain the 1LE valve rather than the stock replacement for my car. my question is; are they the same size/shape? what is the difference in percentage?

stock gm part number: 14089496
1LE gm part number: 10164114

Frankly I want this project to be simple, and to avoid the joy of cutting and remaking flares, leaks, etc. That, and I have already purchased a line lock kit intended for a factory setup (still in box) and don't want to have to try to return it.

thank you all,

Jason

JamesC

iTrader: (5)

Have you replaced the rear pads and calipers (with the Fix-kit in place)? Or if you're looking to upgrade your rear brakes, check the following link:

https://www.thirdgen.org/forums/faq-...iscs-89-a.html

JamesC

thunder85

iTrader: (1)

The pads are new, and the calipers do function (e brake works). what is the fix it kit you are referring to, and what does it repair?

JamesC

iTrader: (5)

Humm, just noted that your car's an 88. The TSB was issued for 82-86 cars with manual trans and rear discs. IIRC, use of the parking brake adjusted the brakes. I'm a bit foggy there though, so perhaps a search is in order.

JamesC

thunder85

iTrader: (1)

right... you are correct. i have done quite a bit of searching on this topic.. there was an issue with the calipers that caused them to seize.. a rebuild or replacement was in order. luckily, i am not in the range of years where that was an issue.

ebmiller88

iTrader: (7)

You are and you aren't. The recall only applied to manual cars, not autos, but all rear discs used the same calipers from '82-88 so this still would apply..technically.

Ed

thunder85

iTrader: (1)

thanks for the clarification.. i misread and apologize for the incorrect information.

ebmiller88

iTrader: (7)

No need for apologies, man, I'm still learning this stuff the farther I go in these cars, but we'll help you as we can.

Ed

ghettocruiser

iTrader: (4)

Im not super familiar with the older rear discs...but Im assuming that they have mechanical e-brake built into the calipers?

If so, the fact that the e-brake works, doesnt nec. mean there is a problem with the calipers/prop. valve. Could be a fluid issue. How are the rear brake hoses...and the hose that goes from the chassis down to the axle? If they've been on there for awhile, they could be partially collapsed or broken down.

Try bleeding the system clean. Put clean fluid in the master, and bleed the rears until it comes out clean. If you get a trickle of fluid, you might have hose issues.

If you are positive all the hoses are ok back there, and everything points to the prop valve, then go ahead and try a new one. Then again...you may have already checked all the other stuff...

J.

thunder85

iTrader: (1)

the lines seem to be in good shape, i have done only visual inspections. with the installation of the new prop block and line lock, I was going to put new braided line in to get rid of the rubber completely. rather than take any risks, i am just going to replace all the possible suspects. frankly, while it isn't the cheapest solution, i would rather err on the side of caution and safety. u figure that should have me covered? whats the likely hood of an issue with the calipers themselves?

JamesC

iTrader: (5)

They nearly always do, but it's the internal collapse that causes the problem. Because these lines are probably nearing their 20th B-day, replacing them (front and rear) can't be a bad idea. In that vein, the calipers may be that old as well. Perhpas it's time for rebuild or replacement (the braided lines will probably cost more than the four calipers together).

JamesC

ghettocruiser

iTrader: (4)

My opinion on the rear calipers is....I would replace them before I rebuild them. That depends on how much they cost though. I dont know what the price of them is...but it cant be too bad.

It definetly wouldnt be a terrible Idea to pull them off when you replace the lines and give them a once over. Make sure everything moves freely and isnt leaking etc etc.

Shouldnt be too bad cost wise to replace the hoses and calipers just as a precaution. But like I said, i dont know how much calipers are for the older rears...

J.