3 times my brake pedal got hard & I had to stomp on pedal to get it to apply brakes. I went to dealer where I I bought TK Tech check every thing he knew to check found nothing wrong. next day on my way to work. I heard a bang from under hood like a cherrybomb, imediately my steering got real sluggish when I applied brakes there were no brakes, just a hard pedal. I paniced, put it in N & stood on park brake. on lifting hood after I got stopped the cylinder to left of master cylinder had blown off, brake fluid all over. no brakes,no steering, I could not even turn steering wheel. TK is at dealership now. has anyone had this problem?http://www.dieselplace.com/forum/smileys/smiley7.gif Edited by: chickentruck

ckd with tech at dealer mon., he said it was the gas charged cylinder beside the brake mastercylinder I asked what caused it to build enough presser to blow off? he said it did"nt build presser also, it didn"t have brakefluid, had power steering fluid, I was concerned about brake fluid all over destroying my paint.http://www.dieselplace.com/forum/smileys/smiley18.gif is that correct, about the powersteering fluid & not brake fluid?http://www.dieselplace.com/forum/smileys/smiley5.gif and i"m courious, why did it wait for 3600 miles before it blew. as for backup system, forget it when that blows if I had been towing I would have been up the creek the brakes & steering were completely goneEdited by: chickentruck

That is the hydro-boos system. The brake assist runs off the power steering pump since a diesel makes no vacuum. The cylinder that came off is a small reservoir that will allow for power assist on the brakes if the engine quits. It will allow for about 2 brake applications then the peddle will get hard to push. The dealer is correct in that it uses power steering fluid, not brake fluid.

my tk has been at dealer shop since 10/1 this is 10/8 they still don't have turbo pipe. they told me today gm engineers are looking at this as this is the first time this has happened, they took pictures of all the damage & emailed to gm I don't know if I can trust this tk now. my wife for sure is afraid to drive it I din't know what my options are but I'm going to get in touch with my factory rep, doubt if it will do any good I know they are trained to passify not make good, would make good duhttp://www.dieselplace.com/forum/smileys/smiley7.gifmocrats any way I'll probley be stuck with a piece of s#@t tk

As aggrevating as this is, it must be a one in a million problem. The hydraboost has been around for decades, and works really well w/o problems. I have had it on 5 vehicles and never had a problem. I had an '80 Olds wagon that had it, it had 245K miles when I junked it, never had any trouble. My '91 has it, no problems at 130K.

This system is much better than the typical vaccu-boost system and it sounds more like a problem with the power steering pump. IMHO

got my tk back, made a trip to daytona fla, no problems at all guess it is fixedhttp://www.dieselplace.com/forum/smileys/smiley1.gif Edited by: chickentruck