'95 Jimmy Brake Probs
Question:
- Hide quoted text — Show quoted text -> My 1995 GMC Jimmy is having a strange brake problem. Initially when I’d > step on the brakes and apply a medium pressure, I’d here a hissing noise > from down by the brake pedal (like a "shhhhhhhhhh") that would continue > as long as I held pressure. > Now the brakes are either real spongy and have to be pressed almost to > the floor, or they get hard and I have to apply lots of pressure in > order to stop. > GM apparently has a problem with the vacuum brake booster (that is what your > problem is). It happened to my 1996 AND 1997 4dr Chevy Blazers (both have > 4WD). It IS a very expensive repair! The failure on my 1997 Blazer occurred > JUST out of the 3 yr bumper to bumper warranty and I did get the dealer to > do a "good will" repair (I paid $200 and they covered the rest). On my 1996 > it occurred around 70,000 miles and it was very expensive. I saved the bills > and will be writing GM regarding this failure. A failure of this type is not > acceptable for model year after model year and under 100,000 miles!! Poor > parts quality!
This GMC is the worst car I’ve ever owned. It’s been in the shop so many times I can’t even keep track, but the brakes have always been a problem. I had written a letter to GMC a few years ago about it (four pages worth of items), but I got a form letter back saying that after reviewing my complaint they decided the car was operating within normal parameters. They basically don’t care about repeat business. > Good Luck!
Thanks. I’ll need it. — Phalanx2 We live in darkness http://members.nbci.com/Phalanx2/ ICQ #84011614
Response:
The brake booster has a nylon valve, connecting the vacuum line to the booster. These valves act up due to moisture / dirt. Replace the check valve [ dealer item ] some cars have a filter to keep fuel vapor out of the booster.
Response:
The Shhhhhhhhh is probably the booster itself which could caused to go bad by the leaking of brakefluid from the master cyl which would account for the spongy feel and low pedal. carl
– Hide quoted text — Show quoted text -> My 1995 GMC Jimmy is having a strange brake problem. Initially when I’d > step on the brakes and apply a medium pressure, I’d here a hissing noise > from down by the brake pedal (like a "shhhhhhhhhh") that would continue > as long as I held pressure. > Now the brakes are either real spongy and have to be pressed almost to > the floor, or they get hard and I have to apply lots of pressure in > order to stop. > I bled all four wheels but it didn’t do anything. I was thinking about > bleeding the ABS unit, but it doesn’t quite match what the manual has > and I don’t want to mess it up. The manual (Chilton’s 1983-95 repair > manual for the Jimmy) says to apply a valve decompressor tool to each > accumulator bleed stem, and one on the combination valve. The valve > decompressor tools I have won’t fit over the accumulator bleed stems, > which I’m assuming are the two stems on the back of the unit. Also, I > don’t see a stem on the combination valve (unless I’m looking at the > wrong thing). > Any ideas on a) what might be wrong with the brakes and b) what’s the > best way to bleed the ABS, other than taking it to the dealer? > Thanks for any help! > — > Phalanx2 > We live in darkness > http://members.nbci.com/Phalanx2/ > ICQ #84011614
Response:
> My 1995 GMC Jimmy is having a strange brake problem. Initially when I’d > step on the brakes and apply a medium pressure, I’d here a hissing noise > from down by the brake pedal (like a "shhhhhhhhhh") that would continue > as long as I held pressure.
Well, I took it to a local dealer and they said it’s the power booster AND the master cylinder. Ouch. I always feel like I’m getting screwed, but I have no choice. He also said the rear shoes were worn down and needed to be replaced (they were supposedly done less than a year ago) and one of the front calipers had a problem where the pad was worn unevenly. The grand total is around $1,700. — Phalanx2 We live in darkness http://members.nbci.com/Phalanx2/ ICQ #84011614
Response:
> My 1995 GMC Jimmy is having a strange brake problem. Initially when I’d > step on the brakes and apply a medium pressure, I’d here a hissing noise > from down by the brake pedal (like a "shhhhhhhhhh") that would continue > as long as I held pressure. > Now the brakes are either real spongy and have to be pressed almost to > the floor, or they get hard and I have to apply lots of pressure in > order to stop.
GM apparently has a problem with the vacuum brake booster (that is what your problem is). It happened to my 1996 AND 1997 4dr Chevy Blazers (both have 4WD). It IS a very expensive repair! The failure on my 1997 Blazer occurred JUST out of the 3 yr bumper to bumper warranty and I did get the dealer to do a "good will" repair (I paid $200 and they covered the rest). On my 1996 it occurred around 70,000 miles and it was very expensive. I saved the bills and will be writing GM regarding this failure. A failure of this type is not acceptable for model year after model year and under 100,000 miles!! Poor parts quality! Good Luck! — Lou
Response:
I haven’t a clue. I think I had a re-built unit put in my 94 but, again, it’s a different vehicle… – Hide quoted text — Show quoted text – > I just called the dealer. Is there no brake master cylinder rebuild kit for > this car? He said there wasn’t, and new master cyliner would cost some > bucks. > My 1995 GMC Jimmy is having a strange brake problem. Initially when I’d > step on the brakes and apply a medium pressure, I’d here a hissing noise > from down by the brake pedal (like a "shhhhhhhhhh") that would continue > as long as I held pressure. > Now the brakes are either real spongy and have to be pressed almost to > the floor, or they get hard and I have to apply lots of pressure in > order to stop. > I bled all four wheels but it didn’t do anything. I was thinking about > bleeding the ABS unit, but it doesn’t quite match what the manual has > and I don’t want to mess it up. The manual (Chilton’s 1983-95 repair > manual for the Jimmy) says to apply a valve decompressor tool to each > accumulator bleed stem, and one on the combination valve. The valve > decompressor tools I have won’t fit over the accumulator bleed stems, > which I’m assuming are the two stems on the back of the unit. Also, I > don’t see a stem on the combination valve (unless I’m looking at the > wrong thing). > Any ideas on a) what might be wrong with the brakes and b) what’s the > best way to bleed the ABS, other than taking it to the dealer? > Thanks for any help! > — > Phalanx2 > We live in darkness > http://members.nbci.com/Phalanx2/ > ICQ #84011614 > — > Phalanx2 > We live in darkness > http://members.nbci.com/Phalanx2/ > ICQ #84011614
– Reach me by ICQ. My ICQ# is 8023912 or, * Page me online through my Personal Communication Center: http://wwp.icq.com/8023912 (go there and try it!) or, * You may visit my Personal ICQ Homepage: http://members.icq.com/8023912 Download ICQ at http://www.icq.com/download/ For adding similar signatures to your e-mail go to: http://www.icq.com/email/emailsig.html
Response:
I just called the dealer. Is there no brake master cylinder rebuild kit for this car? He said there wasn’t, and new master cyliner would cost some bucks. – Hide quoted text — Show quoted text – > My 1995 GMC Jimmy is having a strange brake problem. Initially when I’d > step on the brakes and apply a medium pressure, I’d here a hissing noise > from down by the brake pedal (like a "shhhhhhhhhh") that would continue > as long as I held pressure. > Now the brakes are either real spongy and have to be pressed almost to > the floor, or they get hard and I have to apply lots of pressure in > order to stop. > I bled all four wheels but it didn’t do anything. I was thinking about > bleeding the ABS unit, but it doesn’t quite match what the manual has > and I don’t want to mess it up. The manual (Chilton’s 1983-95 repair > manual for the Jimmy) says to apply a valve decompressor tool to each > accumulator bleed stem, and one on the combination valve. The valve > decompressor tools I have won’t fit over the accumulator bleed stems, > which I’m assuming are the two stems on the back of the unit. Also, I > don’t see a stem on the combination valve (unless I’m looking at the > wrong thing). > Any ideas on a) what might be wrong with the brakes and b) what’s the > best way to bleed the ABS, other than taking it to the dealer? > Thanks for any help! > — > Phalanx2 > We live in darkness > http://members.nbci.com/Phalanx2/ > ICQ #84011614
– Phalanx2 We live in darkness http://members.nbci.com/Phalanx2/ ICQ #84011614
Response:
Thanks. The manual says it covers the 1995, and normally has a special section for the ‘95 where applicable, but who knows. I may hit the book store and see if there’s a better one. – Hide quoted text — Show quoted text – > Your Chilton’s may be the wrong one, the trucks were new in 95, so some > things that worked for 1983-1994 may not work on a 95. I’d suspect the > booster or master cylinder being bad… > My 1995 GMC Jimmy is having a strange brake problem. Initially when I’d > step on the brakes and apply a medium pressure, I’d here a hissing noise > from down by the brake pedal (like a "shhhhhhhhhh") that would continue > as long as I held pressure. > Now the brakes are either real spongy and have to be pressed almost to > the floor, or they get hard and I have to apply lots of pressure in > order to stop. > I bled all four wheels but it didn’t do anything. I was thinking about > bleeding the ABS unit, but it doesn’t quite match what the manual has > and I don’t want to mess it up. The manual (Chilton’s 1983-95 repair > manual for the Jimmy) says to apply a valve decompressor tool to each > accumulator bleed stem, and one on the combination valve. The valve > decompressor tools I have won’t fit over the accumulator bleed stems, > which I’m assuming are the two stems on the back of the unit. Also, I > don’t see a stem on the combination valve (unless I’m looking at the > wrong thing). > Any ideas on a) what might be wrong with the brakes and b) what’s the > best way to bleed the ABS, other than taking it to the dealer? > Thanks for any help! > — > Phalanx2 > We live in darkness > http://members.nbci.com/Phalanx2/ > ICQ #84011614 > — > Reach me by ICQ. My ICQ# is 8023912 or, > * Page me online through my Personal Communication Center: > http://wwp.icq.com/8023912 (go there and try it!) or, > * Send me E-mail Express directly to my computer screen > * You may visit my Personal ICQ Homepage: http://members.icq.com/8023912 > Download ICQ at http://www.icq.com/download/ > For adding similar signatures to your e-mail go to: > http://www.icq.com/email/emailsig.html
– Phalanx2 We live in darkness http://members.nbci.com/Phalanx2/ ICQ #84011614
Response:
Your Chilton’s may be the wrong one, the trucks were new in 95, so some things that worked for 1983-1994 may not work on a 95. I’d suspect the booster or master cylinder being bad… – Hide quoted text — Show quoted text – > My 1995 GMC Jimmy is having a strange brake problem. Initially when I’d > step on the brakes and apply a medium pressure, I’d here a hissing noise > from down by the brake pedal (like a "shhhhhhhhhh") that would continue > as long as I held pressure. > Now the brakes are either real spongy and have to be pressed almost to > the floor, or they get hard and I have to apply lots of pressure in > order to stop. > I bled all four wheels but it didn’t do anything. I was thinking about > bleeding the ABS unit, but it doesn’t quite match what the manual has > and I don’t want to mess it up. The manual (Chilton’s 1983-95 repair > manual for the Jimmy) says to apply a valve decompressor tool to each > accumulator bleed stem, and one on the combination valve. The valve > decompressor tools I have won’t fit over the accumulator bleed stems, > which I’m assuming are the two stems on the back of the unit. Also, I > don’t see a stem on the combination valve (unless I’m looking at the > wrong thing). > Any ideas on a) what might be wrong with the brakes and b) what’s the > best way to bleed the ABS, other than taking it to the dealer? > Thanks for any help! > — > Phalanx2 > We live in darkness > http://members.nbci.com/Phalanx2/ > ICQ #84011614
– Reach me by ICQ. My ICQ# is 8023912 or, * Page me online through my Personal Communication Center: http://wwp.icq.com/8023912 (go there and try it!) or, * Send me E-mail Express directly to my computer screen * You may visit my Personal ICQ Homepage: http://members.icq.com/8023912 Download ICQ at http://www.icq.com/download/ For adding similar signatures to your e-mail go to: http://www.icq.com/email/emailsig.html
Response:
My 1995 GMC Jimmy is having a strange brake problem. Initially when I’d step on the brakes and apply a medium pressure, I’d here a hissing noise from down by the brake pedal (like a "shhhhhhhhhh") that would continue as long as I held pressure. Now the brakes are either real spongy and have to be pressed almost to the floor, or they get hard and I have to apply lots of pressure in order to stop. I bled all four wheels but it didn’t do anything. I was thinking about bleeding the ABS unit, but it doesn’t quite match what the manual has and I don’t want to mess it up. The manual (Chilton’s 1983-95 repair manual for the Jimmy) says to apply a valve decompressor tool to each accumulator bleed stem, and one on the combination valve. The valve decompressor tools I have won’t fit over the accumulator bleed stems, which I’m assuming are the two stems on the back of the unit. Also, I don’t see a stem on the combination valve (unless I’m looking at the wrong thing). Any ideas on a) what might be wrong with the brakes and b) what’s the best way to bleed the ABS, other than taking it to the dealer? Thanks for any help! — Phalanx2 We live in darkness http://members.nbci.com/Phalanx2/ ICQ #84011614
