Tonyrodz's Tahoe Build Thread

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Tonyrodz

Tonyrodz

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Wahhapend?
Fuel injector was pi$$ing gas through the grill onto the road. Weird.
i think most of us expect to see a ford on a tow truck. lol
Can't argue with that--Although--my most reliable car is my Crown Vic. Figure that $hit out. I had a leaking brake line that pi$$Ed out all the fluid for the front brakes--and I drove it like that for a few weeks lol. And I didn't even know!
 
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Tonyrodz

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I need opinions--Driving home from work last night, while stopped at a light my brake pedal slowly went down lower then it should've. Driving it progressively got worse. I changed the master cylinder 2 years ago this month. Changed using an AC Delco part. Do you guys think it sound like the mc again? There's no leaks coming from anywhere, although the mc is a tad low on fluid? My question is could it be the booster instead of the mc? How to differentiate between the 2? TIA.
 

strutaeng

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I need opinions--Driving home from work last night, while stopped at a light my brake pedal slowly went down lower then it should've. Driving it progressively got worse. I changed the master cylinder 2 years ago this month. Changed using an AC Delco part. Do you guys think it sound like the mc again? There's no leaks coming from anywhere, although the mc is a tad low on fluid? My question is could it be the booster instead of the mc? How to differentiate between the 2? TIA.
Did you notice the level of the brake fluid dropped? Like, was the level ever higher?


Maybe you are only losing fluid if you are driving and braking harder? Have a helper pump the brakes while you look around underneath and at each wheel.

I only had those symptoms on a hydroboost system on my old OBS (brake pedal went to the floor while at a stoplight)...turned out the p.s. pump snapped the shaft. All brake AND steering assist were both lost. Not fun.

I believe if the diaphragm on the vacuum booster fails you get a lean condition on the engine, no?
 
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Tonyrodz

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Did you notice the level of the brake fluid dropped? Like, was the level ever higher?


Maybe you are only losing fluid if you are driving and braking harder? Have a helper pump the brakes while you look around underneath and at each wheel.

I only had those symptoms on a hydroboost system on my old OBS (brake pedal went to the floor while at a stoplight)...turned out the p.s. pump snapped the shaft. All brake AND steering assist were both lost. Not fun.

I believe if the diaphragm on the vacuum booster fails you get a lean condition on the engine, no?
I'll check this weekend. The fluid was only low a "hair". Not much. Behind the wheels looked dry.
If a bad booster causes a lean condition I'd be happy--I'd know which was bad lol. I started to notice the pedal getting lower when I was stopped at a red light, before that there wasn't any hard braking.
 

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I'll check this weekend. The fluid was only low a "hair". Not much. Behind the wheels looked dry.
If a bad booster causes a lean condition I'd be happy--I'd know which was bad lol. I started to notice the pedal getting lower when I was stopped at a red light, before that there wasn't any hard braking.
Have you considered a hydroboost swap?

Probably a bad sales pitch after my last post. LoL

And not sure what could be your issue yet, so you may not care about that as much as fixing the issue?
 

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I need opinions--Driving home from work last night, while stopped at a light my brake pedal slowly went down lower then it should've. Driving it progressively got worse. I changed the master cylinder 2 years ago this month. Changed using an AC Delco part. Do you guys think it sound like the mc again? There's no leaks coming from anywhere, although the mc is a tad low on fluid? My question is could it be the booster instead of the mc? How to differentiate between the 2? TIA.
check your brake pads also, when the pads are thin there is more fluid in the system and the reservoir will be lower, so will the pedal feel, just kinda how it works....
 
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Tonyrodz

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I would unbolt the m/c and look at the back to see if is wet or dry. You may also have seepage elsewhere besides the back of wheels.
Will seepage behind the mc give a definitive answer one way or the other?
check your brake pads also, when the pads are thin there is more fluid in the system and the reservoir will be lower, so will the pedal feel, just kinda how it works....
I've driven cars with really low pads. Definitely not that. Thx tho.
 
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Tonyrodz

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Have you considered a hydroboost swap?

Probably a bad sales pitch after my last post. LoL

And not sure what could be your issue yet, so you may not care about that as much as fixing the issue?
I had hydroboost on my Express van. It was AMAZING! It probably weighed 10k pounds. That sucker would stop on a dime.
 

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Will seepage behind the mc give a definitive answer one way or the other?

I've driven cars with really low pads. Definitely not that. Thx tho.
That pocket at the back, should be dry. If is wet, then the m/c is leaking there. If is dry, I would look from front to rear and follow everywhere the lines/connections run. The m/c can bypass internally and cause a funny pedal but still not leak out the back.
 

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I had hydroboost on my Express van. It was AMAZING! It probably weighed 10k pounds. That sucker would stop on a dime.
Yes. Pretty sure all modern 2500+ trucks have hydroboost. It's something like 1,000 psi vacuum-assist hydraulic pressure vs 3,000 psi for hydroboost. Those vehicles have high GVWR, so hydroboost is the only option.

I will probably do the hydroboost swap on my 99 Silverado ECSB 1500 soon. All my other SUVs, the K3500 and our Express passenger van have hydroboost. Well, our minivan doesn't either.

It's just the hydroboost, lines and PS pump (some guys just tee into the PS return hose and keep their PS pump) for the 1500 swap.
 
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strutaeng

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Just curious--what exactly would be needed to retrofit the hydroboost on my 03?
Here's a tutorial. It's for a Silverado, but I'm assuming it should be the same for your Tahoe?


It actually seems pretty straightforward.
 

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