Is it just me or are these old trucks hard to stop. My '92 W350 seems to need a lot of petal pressure to completely stop in traffic and when I shut the engine off at DQ, so the girl can hear my order, the darn thing starts rolling backwards within a few seconds and it takes two feet on the whoa petal to stop. I realize that 7300 pounds is a lot of weight, but should I loose vacuum boost that quickly after shutdown?

 

I can hold mine all day long without a problem(with it shut off) as long as I don't play with the pedal. You may want to check your fluid level also, sounds like a leak of some kind.

Good luck,
Michael

 

mine stops like a car, and i also dont have probs holding it engine off. Id check make sure you have enogh vacuhm and to see if the booster holds it. It sounds like the booster is leaking or theres a vacuhm leak somewhere.

 

Once I started adjusting my rear brakes I never had trouble stopping mine. If it's pushing you at idle you may want to drop the idle speed a hair.

 

The idle is ok and I don't have fluid leaks. Sounds like I need to check out the vacuum side of the booster and the vacuum pump. How much vacuum can a good pump suck?

 

Spec is 8.5 - 20 in. I'd say a healthy one ought to be able to pull 15" or so. The idiot light comes on if the vacuum drops below 8.5 for more than 10 seconds.

 

8.5 - 20 ???


I swear mine pulls 25 or better.

maybe my gage is bad.....

 

Pesky 2nd gen guys with their high suction vacuum pumps...

 

I could have swore the last time I checked mine on the 93 it was around 25 in or more. I'll check it tomorrow just while I'm working on it.

 

OK, here is the latest and the greatest.
1) My vacuum pump sucks. It is pulling a 25 in vacuum at idle. The hose had gone soft at the pump fitting so a little trimming and that problem was solved.
2) I performed a drop test on all the lines to the power assist booster and everything is tight. I even performed the drop test as discribed in the offical 'Cry'stler Shop manual. Everything looks good. BUT
3) I started the truck allowing vacuum to stabilize at 25"hg and shut the truck off. Vacuum remained at 25"hg for 30 seconds without moving. I then put my foot on the brake lightly and lost about 15"hg which is good. (Here's the BUT)Sometimes the vacuum continues to fall to zero and sometimes if I find the "sweet spot" it will not. Please somebody tell me it will be all right and that I don't need to change the booster!

 

Aw, C'mon, changing the booster isn't bad. There's even enough room to do it without pulling the master off the lines.

 

My 86 would drop vacume when my foot was on the brake. I`d be sitting at a stop light and you could hear the booster hissing and sometimes the engine would develope a lean misfire (gas engine). A new booster fixed it....sorry. And like Wanna said, it`s not too bad to change.

 

The physical labor doesn't bother me at all. In fact I actually like working on my truck. What bothers me the most is the $100.00 that I have to pull from my BOMB BUDGET . I am even entertaining the thought of Killing the Dowel Pin. I can do that for free. I am a cheap skate at heart. My financial priorities are:
1) Beer
2) shelter
3) fuel
4) toys
5) work, so I can buy beer.

 

Mine requires no more pedal pressure than a car...BUT, like a 1-ton '74 Dodge van, I once had(one of those little school buses) and a 90 F350 diesel later, this truck will lock up the front brakes surprisingly fast. Is this just a trend from this era of 3/4 and 1 ton trucks?

(3/4 ton 2WD 5sp reg-cab)

 

I ordered a remaned booster from Advance yesterday ($75.00) and pulled the old one off. It was definitly passed due. It seems there was a little fluid saturating the foam wiper at the brake rod on the inside. Probably should have been replaced when I did the master cylinder a couple months ago. Took 30 minutes and I didn't break the lines. The next time the rear wheels come off I will most likely upgrade the wheel cylinders.