Hydroboost leak

[arveetek]

I've developed a serious leak on my hydroboost brake assist. Every time I apply the brakes, a stream of power steering fluid pours out between the master cylinder and hydroboost system. Is there a seal that goes between the two? Or is this an internal problem with the hydroboost? If so, can I repair/rebuild it, or does it require replacement?

This is on my '95 Tahoe. It's currently leaking enough fluid that I have to refill the power steering reservoir every four to five days.

Thanks,

Casey

[DmaxMaverick]

They don't usually leak at the front seal. When they do, it's game over. Time for a reman unit. There's really nothing you can do at home. Rebuild kits can be had (not cheap), but a successful home rebuild is a gamble at best, after you've done a few. I have, with only about 50% success. It's usually more than just seals and the included kit hardware that fail. Kinda' like master cylinders. And, they're not easy, even when everything goes right. I wish I had better news for you.

[Robyn]

Yesssss
Replace the unit and be selective as to where you get the reman.

I have had a few from parts stores that turned out to be worse than the one that I took off.

Makes one wonder what the rebuilder did other than wash it and spray on some fresh black paint.

I got the last one I used from a local rebuilder and I watched while they rebuilt the core, as they did not have the one I needed in stock.

As Maverick said, doing a home rebuild is sketchy at best.

I have done one and it turned out well but, never again.

I have a fairly well equiped machine shop here as well as close to 40 years wrenching on rigs under my belt too and I would rather eat dirt than do another one of those critters.

When you have all the prescribed "special tools" to do the job, your way ahead of the game. I had to improvise everything to do the work and that makes it just plain no fun.

Personally I would prefer a new unit over a reman but, the cost is $$$$$$$$ as compared to the reman.

If you get a good reman, their fine but its a crap shoot these days as to what your gonna get.

Good luck and keep us posted.


Robyn

[Yukon6.2]

Hi
Any tricks a person should know about changing the hydroboost unit?I found a leak on one in our new to us wrecker.I have a donar truck to harvest a non leaking one from,and am looking for any tips to make the job go smooth,both trucks are 96's
Thanks Thomas

[arveetek]

Well, I replaced the hydroboost unit last night. I had tried using Power Steering Stop Leak but it didn't help any...I had too large of a leak.

I was pleasantly surprised at how easy it was to change out. Two bolts hold the master cylinder on, three hose connections, and then the 4 bolts holding the unit to the firewall. There was also the clip holding the pushrod to the brake pedal. All in all, quite simple. I didn't even have to remove any dash components for access...it was all fairly easy to get to by laying on my back.

I purchased a rebuilt unit from my local auto supply for $170 exchanged. Seems to be a good unit so far.

I also put new rotors, calipers, hoses, and brake pads on the front.....they were long overdue for some maintenance.

Casey

[WyoDutch]

I've gone through 2 units on my 1984 K2500. The first one went out in 1986... It leaked from the arse end... the fluid running down the shaft, through the firewall and saturated the insulation/soundproofing and carpeting. Worst mess I ever saw.

Second unit went out in the mid 90's. Didn't make quite the mess... just dumped brake fluid all over the driveway.

So far, so good on the third unit.

[Robyn]

Been there done that myself.

Yup, does soak up the padding for sure.

Good luck on things


Missy