Thread: lowered vehicle breaking help?

Tweet

I figured you guys would have some good ideas.I have a 89 suburban that I lowered 5"/7".Breaking does not act the same anymore.Before it was even breaking front and back.Now ,I have more breaking in the front than inthe back.The front tires will lock up and while the back is still spinning.Is a proportioning valve the solution?Inlighten me Can someone give a simple explaination of why lowering the center of gravity affected the breaks.

did you re-adjust the pinion angle? Are the shocks at the correct lenghs & angles to work properly? Do you have a panhard bar from the factory? Has it been re-set for angle?
All of these things become a big factor in the chassis performance not only in braking, but in acceleration too. 5/7 is a lot of drop.
I'm not saying that you didn't do it right- just a few points to check. If you have all of these correct I would start looking for a pinched brake line.
If no pinch & everything else is correct than I would install an adjustable porportioning valve.
But I'm a painter so that's just my opinion..
Good Luck

I don't want to insult your intelligence, but are you sure you bled the rear brakes good? Nothing you did should prevent them from working, it has to be something you just overlooked.

Pinion angle is correct ,and switched to a brand new one piece heavy duty drive shaft.This was to keep motor at stock anlge, and less universal joints only two,and eleminating the center bearing .The rear shocks do come to mind though,thats the next thing I am going to change.After useing shock extensions they still get close to bottoming out.On top of that, I have blown a couple of sets(air shocks),maybe 2,but the truck has also been lowered about 2 years ago.I used a complete lowering kit from Bell Tech (flip kit in the rear).I would like to use this vehicle as a tow vehicle,so I am putting in a air bag support system in the rear(then I can use shorter shocks).The air shocks I have are "stock" length heavy duty shocks.I can also manually air up the bags in the back when I carry heavy loads.Also new brake fluid in the whole system would not hurt either.

When I dropped my 69 PU it was "diving" on me and I had to go to a stiffer front shock as well before I could get any rear braking- it still had to have a valve before I could get even braking.

With that much of a drop, I would be looking for pinched or sharp bends in my rear brake lines and hoses.

Not that I think this has any bearing on the break problem but I have a 92 suburban and wanted to go to a one pc. drive shaft. I was told by more than one shop that it would viberate to much and they wouldn't even do it seems there is a length limet on one pc. drive shafts. You may want to check this out.

Originally posted by cffisher
Not that I think this has any bearing on the break problem but I have a 92 suburban and wanted to go to a one pc. drive shaft. I was told by more than one shop that it would viberate to much and they wouldn't even do it seems there is a length limet on one pc. drive shafts. You may want to check this out.

Well with a a one piece drive shaft there are those that say its they only way to go and those who say don't do it. It is a BIGGER diameter drive shaft than stock dia.,Also with the (stock)two piece I would have to add a crap load of spacers to the motor ,trans,and center bearing .Plus one day I do want to bag it,and go lower.I don't know how the bags will affect a occasional tow vehicle though?

The more I think about it I do think it is the rear shocks.I drove it today and purposely tried to brake hard .On a smooth street it was not bad at all ,but on a street with high and low spots the front tires broke loose easily.I think the rear shocks are limiting the unloading of weight in the rear of the vehicle.I am going to ditch the stock shocks ,and try some aftermarket shocks.The correct length.