1999 Tahoe Hydroboost Install

[Whippled2dr]

I installed a hydroboost setup on my 2 door tahoe two weeks ago. The whipple and intercooler will be back on in a couple of weeks.


Parts:
- Hydroboost and Master cylinder from local junk yard (98 HD truck)
- New AC Delco steering pump for a hydroboost truck
- Ebay Mounting plate with centered whole
- Hydratech aeroquip hose and fitting kit for my application
- Various stainless nuts and bolts from mcmaster
- 3/8-16 thread die for the hydroboost pushrod
- Ac delco brake light switch
- Steering and brake fluid

I took the snap ring off the unit and unscrewed the retaining nut with a big adjustable wrench and test fitted the new plate. All fit perfectly and the holes of the new plate matched the stock plate holes.

(I used this centered plate because I used the stock brake pedal).
I bought the plate from ebay from the seller sterlingworth16. It is 3/16" thick steel.
http://motors.shop.ebay.com/merchant/sterlingworth16_W0QQ_nkwZQQ_armrsZ1QQ_fromZ

Pic of the master cylinder.

I cut and threaded (3/8-16) the pushrod making it shorter by +- 5 mm. Once I get my vacumm booster off I'll measure and adjust the rod to the same length. The joining nut is stainless and 1-1/8" long. By doing this and using the center mounting plate, I can reuse my stock brake pedal.

End result:

Hydratech hose and fitting kit for a 99 tahoe. These are Aeroquip TFE high pressure hose and fittings. Great service and packaging on hydratech's part.

Before

After

Filthy!

This setup has been on for about two week so far and has worked great. I actually had my first panic stop yesterday and was glad I did the swap.

 

[AtomicHoe094]

what was your overall amount of money spent?? looks good

 

[mikeykey]

Never one to worry about looking stupid here. What is a hydroboost and whats it do?

I can see it obviously takes the place of your brake booster. Is this the great fix to our ****** brakes?

Oh....and that whippled hoe is bad ass.

 

[Whippled2dr]

what was your overall amount of money spent?? looks good

- Hydroboost and Master cylinder from local junk yard (98 HD truck) - $100
- New AC Delco steering pump for a hydroboost truck - $80
- Ebay Mounting plate with centered whole - $30
- Hydratech aeroquip hose and fitting kit for my application - $200
- Various stainless nuts and bolts from mcmaster - $30
- 3/8-16 thread die for the hydroboost pushrod - $15 (bought a set to have)
- Ac delco brake light switch - $5
- Steering and brake fluid - $? (2qts of steering and large bottle of brake fluid)

So about under $500 for everything. The Hydratech kit costs $700. You can do the swap for far less if you don't flip your hydroboost and use stock hoses.

 

[GreyFox]

Never one to worry about looking stupid here. What is a hydroboost and whats it do?

I can see it obviously takes the place of your brake booster. Is this the great fix to our ****** brakes?

Oh....and that whippled hoe is bad ass.

http://www.superchevy.com/technical/chassis/brakes/0601sc_hydro/index.html

Heck I had to look it up.
in short yes it should be an upgrade. But the stock lines may not be able to handle the increased pressure.

---------- Post added at 09:13 PM ---------- Previous post was at 09:12 PM ----------

if i'm wrong please correct me.

 

[General Stalin]

If you don't feel like clicking and reading the link: Hydroboost is the brake system that many 3/4-ton and 1-ton trucks use. Instead of have vacuum assisted brakes, hydroboost is, as the name implies, hydrolically assisted. It's a lot more powerful and increases stoping ability significantly. I need to do this upgrade to my truck once I get my new engine in there.

I actually have heard the hydroboost setup is more beneficial than converting to rear around disc brakes.

 

[GreyFox]

If you don't feel like clicking and reading the link: Hydroboost is the brake system that many 3/4-ton and 1-ton trucks use. Instead of have vacuum assisted brakes, hydroboost is, as the name implies, hydrolically assisted. It's a lot more powerful and increases stoping ability significantly. I need to do this upgrade to my truck once I get my new engine in there.

I actually have heard the hydroboost setup is more beneficial than converting to rear around disc brakes.

but is the cost worth it. I talked to my buddy about it and he said he hated it when it first came out. To be more exact when they were putting it on cars and trucks that had no business having hydro boost. That and he said it was too expensive to repair if it went bad. the number he told me was about $700 and that was over 30 yrs ago.
Also does it affect ABS?

 

[Boost infection]

Also does it affect ABS?

+1

 

[destroyer1362]

+2

 

[clean454]

+3
yeah Whipple go stomp on them really hard and see if it locks up i bet it does, lol make sure ur seat belts on tho!

 

[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!!