GMT 400 Hydroboost swap

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kylenautique

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I do plan on a big brake upgrade just not right now -- is this something I would have to do now ?

Not Yet, I'm in the middle of doing a LS swap so was just doing the brake swap while i was at it
Yes you have to upgrade the calipers. You can’t run the half ton low drag calipers with the 1 ton master cylinder. They aren’t very expensive. You use your stock pads and rotors. You just expand the brake pad metal retainer to fit the larger piston.
 

Jesse_Wenting

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Has anyone done this swap with a tee fitting on the return lines experienced a leak at the tee?

Started my truck to drive home yesterday after work and the return line from the gear worked loose at the tee. Took me long enough to find it that it ran the reservoir empty. I secured the return line, refilled the reservoir, ran the engine for about 5 minutes with no change in fluid level before I got power assist back (steering and brake). Proceeded to drive 35km home in a snow squall with near zero visibility.

I've know I need to replace the pump for a while now, and I'm going to get a hydroboost style reservoir and -an lines at the same time, but winter is here and I don't have a shop. How high is the risk of this occurring again if I just clamp the crap out of the hoses at the tee fitting and keep driving? My worry is if this happens while I'm driving on slippery roads..
 
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Supercharged111

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Has anyone done this swap with a tee fitting on the return lines experienced a leak at the tee?

Started my truck to drive home yesterday after work and the return line from the gear worked loose at the tee. Took me long enough to find it that it ran the reservoir empty. I secured the return line, refilled the reservoir, ran the engine for about 5 minutes with no change in fluid level before I got power assist back (steering and brake). Proceeded to drive 35km home in a snow squall with near zero visibility.

I've know I need to replace the pump for a while now, and I'm going to get a hydroboost style reservoir and -an lines at the same time, but winter is here and I don't have a shop. How high is the risk of this occurring again if I just clamp the crap out of the hoses at the tee fitting and keep driving? My worry is if this happens while I'm driving on slippery roads..

I would think the risk of it happening in the first place was pretty low, but with the colder weather it will be more prone to doing it in general. Did you not have it tight enough in the first place?
 
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Jesse_Wenting

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I would think the risk of it happening in the first place was pretty low, but with the colder weather it will be more prone to doing it in general. Did you not have it right enough in the first place?

I got new PS lines all around and a 3/8 tee fitting for the return lines when I did the swap from vacuum. Clamped down the lines at the tee and hadn't touched it since. Only thing I've replaced recently was my brake master cylinder (here) 2 days before this happened.

My PS fluid may have been a little high, and I did notice that the clamp where the leak occurred was on top of the barb where the other 2 were pin front of the barb (only one on each fitting of the tee). I cut a little off the hose before I made the trip home to insure the clamp would be positioned before the barb now.

Edit: If I wait until the end of winter to replace my PS pump and reservoir I will be ditching plastic tee and twist style clamps, and replacing them with a brass tee and crimp style clamps
 

Supercharged111

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Plenty of folks have done it this way with no problems, I'm inclined to thinking clamp placement was the culprit here.
 
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