Height Leveling Valve - Whats It Do?

[1964dart]

Hi All: on my 86 comanche what is the leveling valve above the rearend used for?  Looks like mine hasn't been hooked up some time.  Can I just cap the lines off? I'm in the process of redoing the complete brake system. thx Norm

[yxmj]

It is a brake bias valve it adjusts the brakes when you have a load in the box. It can be bypassed ( i kept mine working) there is a thread on the site on how to do it

 

 

 

Here is one thread- http://comancheclub.com/topic/4016-xj-proportioning-valve/

[92tanMJ]

Here's how to make a new one

 

http://comancheclub.com/topic/16955-adjustable-mj-load-sensing-valve/

[oldseddie]

As service manager of a Jeep dealership during the years these trucks were made, I spent a good bit of time addressing braking problems. It was a poor design as when you nail the brakes the front end dives and the back end rises causing the valve to reduce rear braking. Not a good thing. It is my theory that this is why they quit making them. They were already priced too high for the market segment and adding antilock brakes would have made them even more expensive. 

[cruiser54]

As service manager of a Jeep dealership during the years these trucks were made, I spent a good bit of time addressing braking problems. It was a poor design as when you nail the brakes the front end dives and the back end rises causing the valve to reduce rear braking. Not a good thing. It is my theory that this is why they quit making them. They were already priced too high for the market segment and adding antilock brakes would have made them even more expensive. 

Which dealership and where? I was Service Manager at a dealership form 1980 through 1992.

[oldseddie]

Skyland Automotive in Asheville, NC

[cruiser54]

Skyland Automotive in Asheville, NC

York Motors

 

Prescott, Arizona.

[Eagle]

As service manager of a Jeep dealership during the years these trucks were made, I spent a good bit of time addressing braking problems. It was a poor design as when you nail the brakes the front end dives and the back end rises causing the valve to reduce rear braking. Not a good thing. It is my theory that this is why they quit making them. They were already priced too high for the market segment and adding antilock brakes would have made them even more expensive. 

 

It's not a poor design. Reducing the amount of braking force on the rear wheels when the weight shifts OFF the rear wheels is the best way to avoid spin-outs. It is, in fact, not just a good thing but a VERY good thing. A number of other small and midsize pickups also use similar proportioning valves.

 

Chrysler killed the Comanche because the Comanche was a better truck that could do everything the Dakota could do, in a smaller package. Chrysler didn't want to have the Comanche competing against the Dakota and they weren't about to kill the Dakota ... so they killed the Comanche.

[cruiser54]

 

As service manager of a Jeep dealership during the years these trucks were made, I spent a good bit of time addressing braking problems. It was a poor design as when you nail the brakes the front end dives and the back end rises causing the valve to reduce rear braking. Not a good thing. It is my theory that this is why they quit making them. They were already priced too high for the market segment and adding antilock brakes would have made them even more expensive. 

 

It's not a poor design. Reducing the amount of braking force on the rear wheels when the weight shifts OFF the rear wheels is the best way to avoid spin-outs. It is, in fact, not just a good thing but a VERY good thing. A number of other small and midsize pickups also use similar proportioning valves.

 

Chrysler killed the Comanche because the Comanche was a better truck that could do everything the Dakota could do, in a smaller package. Chrysler didn't want to have the Comanche competing against the Dakota and they weren't about to kill the Dakota ... so they killed the Comanche.

True story. Chrysler's engineers thought they were better than the Jeep engineers. Originally said the 4.0 was gonna go away real quick and the 2.5 was going with it out the door. HaHa, the 2.5 ended up in the Dakota and the 4.0 went on to over 5 million produced. Ram got the XJ based front suspension, too.

 

[oldseddie]

Cruiser did you ever have any dealings with Gregg Gillette in Jeep technical? He was a sharp cookie and one of the few Chrysler retained.

[cruiser54]

Cruiser did you ever have any dealings with Gregg Gillette in Jeep technical? He was a sharp cookie and one of the few Chrysler retained.

I left the dealership in 1992, but that name sounds familiar. I dealt mostly with Lonnie and Big Al. Remember Darrell, the Renault Alliance guy?

[oldseddie]

I had five lines to keep up with and spent a lot of time on Oldsmobile an Eagle problems. After two attempts at repair I had to make sure we had it right or it was buy back time. Mercedes although mostly trouble free required a lot from their service managers. They now have two managers doing what l did, and neither of them has ever been certified.