1999 Tahoe Hydroboost Install

[Whippled2dr]

The braking compared between my tahoe and my brother's 96 2dr is a night and day difference even though we have the same rotors and pads. Another factor is that i have a 9.5" 14bolt rear axle with the larger 13" drum brakes and his is the stock axle with the 10" drums.

 

[sparg93]

Whipple - with the new power steering pump, did you need a larger/smaller serpentine belt? Which power steering pump did you go with?

 

[sparg93]

Also, all those nice and shiny fittings from your hydratech hose kit...are they necessary? I've been trying to rap my brain around why you would need those fittings if those hoses already have them on there....

 

[Whippled2dr]

Whipple - with the new power steering pump, did you need a larger/smaller serpentine belt? Which power steering pump did you go with?

I used a new stock delco pump and reservoir used on a truck that has hydroboost brakes. The ps pulley remained the same so no need to change belt length. The reason i changed my pump was to get the extra inlet on the reservoir but you can just tee the extra line on the return.

Also, all those nice and shiny fittings from your hydratech hose kit...are they necessary? I've been trying to rap my brain around why you would need those fittings if those hoses already have them on there....

No they are not needed. I flipped my hydroboost so I couldn't use stock hydroboost lines. Flipping the hydroboost was needed to clear the whipple compressor.

 

[sparg93]

Whipple - makes sense, thank you!!

Just to confirm, the "reservoir" you mention...that is the reservoir on the PS pump with the two connections sticking out of it? When you ordered the PS pump, I'm assuming it came as a complete unit.

Also, an article I read had the guy switching out the power steering box...but I can't see why you would need to do this. I didn't see anywhere in your write-up about your switch to the new box...has the steering feel changed at all when you drive? When you smash on the brakes, can you still turn your wheel?

 

[Whippled2dr]

Whipple - makes sense, thank you!!

Just to confirm, the "reservoir" you mention...that is the reservoir on the PS pump with the two connections sticking out of it? When you ordered the PS pump, I'm assuming it came as a complete unit.

Yes but i had to transfer over the electronic valve from the back of my pump which is used for the speed sensitive steering. New pump is not necessary, just T the extra return line with the original return line going into the reservoir.

 

[sparg93]

I just edited my last post...at the same time you responded

Here is the updated portion of the question:
Also, an article I read had the guy switching out the power steering box...but I can't see why you would need to do this. I didn't see anywhere in your write-up about your switch to the new box...has the steering feel changed at all when you drive? When you smash on the brakes, can you still turn your wheel?

 

[Whippled2dr]

I just edited my last post...at the same time you responded

Here is the updated portion of the question:
Also, an article I read had the guy switching out the power steering box...but I can't see why you would need to do this. I didn't see anywhere in your write-up about your switch to the new box...has the steering feel changed at all when you drive? When you smash on the brakes, can you still turn your wheel?

Only issue i have right now is that when I push the brakes while turning a little, there is a little jolt in the steering. Not sure if anyone else experiences this but I'm assuming it has something to do with the speed sensitive steering. I do not believe any hydroboost trucks have the variable assist steering so i think if you use a PS pump without the EVO valve on the back then you'll need a steering gear from a 96 truck.

One thing I'm going to try is to use GM's elimination kit for the variable assist steering and see if it cures my jolt.
http://www.pacificp.com/forum/viewtopic.php?t=10246
GM#19168825

 

[sparg93]

definitely post your results....i found a few more articles and it seems that jolt is fairly common for hydroboost conversion on rigs with variable assist steering.

 

[sparg93]

I just came across this old thread while searching for a few items...

I went ahead and installed a hydro unit so here are my thoughts:

I purchased a complete (new) ACDelco system that would have fit a '99 3/4t Suburban w/rear drums. Here's a link to all the part #'s http://www.gmc4x4.com/topic/120-hydroboost-conversion-part-s/?hl=hydroboost

For this to work properly and not overheat, you really need to purchase everything in the part list (then there's no need for a "t" connector). Also, you have to remove the variable speed sensor for the system to function properly and install the GM bypass.

Also, the hydro brake pedal were notoriously difficult to find, but LMC now sells them brand new for $35 IIRC.

One important aspect to pay attention to -- different hydro units and PS pumps have different pressure ratings...so try not to mix & match. Find one truck you want to mock your system off of and stick with that setup.

I hope this helps!!