Am I correct that the problem is the master cylinder?

[dinosore]

I brake come to a complete stop and while putting pressure my foot eventually starts to sink down more. If i were to come to a complete stop and hold the pressure but make sure my foot doesnt sink the truck starts to roll... Im pretty sure this is my brakes master cylinder going bad correct?

Thanks all.

 

[dinosore]

side note: is it worth it to spend the money on a very price motor craft master cylinder? or is an aftermarket one suitable?... Motor craft =$250 Aftermarket Brands = $40-$60 pretty big price hop in my opinion.

 

[BRUTUS_T_HOG]

You are correct, but do check for any fluid leaks in other parts of the system before condemning the master cylinder.

A motor craft master would be a excellent buy. I have had zero issues so far with NAPA new masters and cardone remanufactued.

 

[jhammel85]

I agree...if you aren't leaking then yeah its the master cylinder. Rebuilds are fine. Check RockAuto.com because a motorcraft master cylinder might be cheaper there.

 

[dinosore]

Thanks. I'll check the lines and look for signs of leaks. I was looking into NAPA as I haven't had problems with their parts in the past. Jhammel RA was the $225 w/o shipping for the motorcraft. Honestly wish I could afford it cause MC makes great products but i just can't spend the on a master cylinder on a 22yr ol truck.

 

[Mark_88]

I had a similar issue and found it was just a tiny leak at one of the joint connectors I used to splice the rear lines together. Once that was fixed I had no problems...but had to bleed the system again to get all the air bubbles out.

Might want to change the brake fluid also since it can get moisture inside that causes similar symptoms. Recommended maintenance is to change brake fluid after a few years...so replacing brake lines that are badly rusted is a good idea also...

 

[martianable]

You might also want to test the mystery valve

I heard this is also a part of keeping things tight on the rear brakes - do you have a check valve like this ?

http://www.therangerstation.com/forums/showthread.php?t=152212

 

[dinosore]

Nope mine does not have a valve as pictured. I will continue to check the lines but havent found anything yet. I did however find What looks like a fluid ( possibly brake fluid) going down the firewall near the brake and clutch master cylinders... With that being said I am more inclined to think its my brake master cylinder, I do need to change my clutch master as well as it is squeaking like hell. I know brake fluid can make things squeak and since the clutch master sits below the brake master I'm now thinking that the brake master is leaking somewhere causing me to lose pressure in the brake system and that fluid is leaking and some how getting through a seal near the clutch master which may be causing the squeal I hear when pressing and depressing the clutch pedal...

the above scenario explains both my situations and is the only one I can come up with after looking around the trucks brake lines and such...

 

[Mark_88]

Did you try having someone else pump the brakes and then the clutch so you can watch? Put rags around each of them...those blue shop towels work very well...pump the heck out of them and check for the wet spot...

Sounds a bit like sex but usually you find the wet spot first before pumping the heck out of them...then you check the mattress for the wet spot...or change the sheets.