p/s pump due for a replacement

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SnowDrifter

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Mine's old and tired. She's pushing 170k. No leaks, but it's definitely lacking in the pressure department. Hot steer at parking lot speeds is getting stiff, and hydroboost is beginning to lack. Have trouble engaging ABS at full pedal application. Slightly thicker fluid seems to help, but that's a really bandaid tier fix for short term.

Any suggestions on after market? HD unit / higher pressure / higher flow? Or is OEM best route here? I'm a bit skittish of cheapo reman pumps... Always had issues with the things performing.
 

Mudsport96

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Not sure if these pumps are the same/similar design as the pumps used on the 96+ vortec trucks. But, on those when they got weak ( for us offroad guys) we would replace the pressure relief spring/valve. Years of cycling rook tension out of the spring and there wasnt anything really wrong with the pump other than the relief leaking pressure.
It has been a few years, but if i remember a 2500/3500 relief was about 100 psi higher than the s10/1500 relief and screwed right into the pump. Or a new 1500 with an extra shim or 2 to boost preasure.
May be cheaper to start with the valve. If i remember its less than 30 bucks vs a whole new pump.
 

exp500

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I've had great service from many Lares rebuilt pumps. With Hydroboost, be careful in selection of Orfice/relief or brakes when slow not what you want. I too have been swapping Relief Valve assemblies, springs, and orifaces for many tens of years, usually to improve steering feel. You need spring measuring tools, pressure gauge adaptors, and multiple orfice mikes.
 
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SnowDrifter

SnowDrifter

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Ok revisiting this as I now have time to replace the thing.

Pump is definitely worn. Not sure I feel like fussing with shims on a 170k pump given the cost of a replacement. If it was low mileage, I'd feel different. But as is: I could just as easily see me getting the thing working only to have it start leaking and getting angry in 10 or 20k miles. Meh.

So:

Oe AC delco?

Worth putting a shim kit in the new one to up pressure a touch(link to shims? There's a lot..)? Smaller p/s pulley(dirty dingo)? Both? I want assist - ya know... Can turn the wheel as fast as I want at idle in a parking lot, and have gobs of brakes. As of now, I have neither. Can't actually hit the brakes hard enough to engage ABS on dry which was a fun wake-up. And steering is lame if I'm trying to whip into a parking lot maneuver at idle
 

exp500

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I would recommend a larger pump based on your description. Look up the factory pump and relief/flow control valve for yours and a 1ton crew cab. The Bills hot rods shim kit numbers work out to approx 11.63# /.001 for dropping pressure. The flow controls oriface size for the big hydroboost pumps range .187-.210. S10 Oriface about .160 . Lower pressure more road feel. Flow does the work if minimum pressure needed met. Good luck and post results.

Bills Hot Rod Co. 1001 Power Steering Flow Control Valve Kit
 

THarber

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Shimming is not the way to go. What you have to be careful with is if you get a reman unit to make sure it has the higher flowing orfice valve installed and not passenger version. I went thru this with my H2. The orfice size is larger for a truck, allowing more fluid to flow to brakes and steering. I also ended up finding a pump assembly from a van that had a few more 'vanes' that flowed more fluid. My Amazon shows its part # 20756713 I'm not sure if it will fit your truck or not but it made all the difference in the world on my old truck.

Tim
 

swathdiver

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Ok revisiting this as I now have time to replace the thing.

Pump is definitely worn. Not sure I feel like fussing with shims on a 170k pump given the cost of a replacement. If it was low mileage, I'd feel different. But as is: I could just as easily see me getting the thing working only to have it start leaking and getting angry in 10 or 20k miles. Meh.

So:

Oe AC delco?

Worth putting a shim kit in the new one to up pressure a touch(link to shims? There's a lot..)? Smaller p/s pulley(dirty dingo)? Both? I want assist - ya know... Can turn the wheel as fast as I want at idle in a parking lot, and have gobs of brakes. As of now, I have neither. Can't actually hit the brakes hard enough to engage ABS on dry which was a fun wake-up. And steering is lame if I'm trying to whip into a parking lot maneuver at idle
GM OE would be my first choice and ACDelco Gold/Professional if the former is not available. It lasted 170K, why not again? Of course, I have no experience with aftermarket or reman pumps in these new trucks. In older cars, they never got them right, they always whined a short time after installation so I just ponied up the extra cash for new OE.
 
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SnowDrifter

SnowDrifter

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Fair!

Honestly.... I'm probably getting more wound up in my head about pump differences vs. just accepting the damn thing is worn and that's the source of my issues hah. Didn't have this issue when I picked 'er up at 115k. It's just due for a new one!!


One thing I'm not certain about, however, is which pump I actually need. I'm seeing 2 potential units for my truck. AC Delco 15909832 and 88963604. Gotta be honest... I can't tell the difference between them
 

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