Truck dives to the left

[kennybro]

I hope someone can help me... I'm at my wits end!!!
1987 Hardbody 2wd, single cab, 5spd, WITHOUT power steering
about 15k miles

My problem is when braking(hard) the truck pulls or dives to the left. I've replaced the following;

Front brake calipers, hoses, pads, and master cylinder
brake fluid and bled system(of course)
all ball joints and steering rods
bushings ALL front and rear (polyurethane)
alignment to factory specs

My next "guess" is torsion bars... Anybody with this similar problem? PLEASE

[RT22]

Torsion bar or shock, my bet would be torsion bar on that side is not up to snuff. get it on a lift and see if it has play or one is binding or something.

[kennybro]

I'll check that, thanx... BTW I forgot that I did replace the shocks

[jimschouster]

Mine was a bad tire

[kennybro]

replaced all 4 tires...

[Rev_D21]

Only one working caliper?

[kennybro]

I know the brake calipers are working

[Rev_D21]

Then you have something going on in your steering. Perhaps a loose idler arm, center link or worn bushings. Mine used to dive but that stopped once I replaced my brake hoses with braided stainless and adjusted my rear brakes up.

[longtooth]

Ok this may sound weird but are you a big guy? If so things may need to be changed. Had a guy bring his rig in for the same thing. He didnt tell us it was his wifes car and she was a big girl. HD springs on one side and alignment with her weight in the car fixed their problems.

[Desert Rat]

Tension rod bushings. If they're shot, it could be compressing, causing the right wheel to "steer" a bit to the right.

Different air pressures in the tires could do this as well.

[kennybro]

Thanx guys... but everything mentioned above has been addressed and I'm about 180lbs (give or take)

[seang]

Did you bleed the rear proportioning valve? Also, did you bench bleed the master cylinder?

[kennybro]

My truck doesn't have a proportioning valve and yes to the bench bleeding...

[RT22]

The only other thing I can think of is that caliper is grabbing MORE than the other. Semi clogged line, sticking or messed up caliper. Could be worn bushings in one side allowing slop in suspension. Sounds like you have checked most everything else. Just give the entire fron suspension the once over, make sure all is tight and able to move with no binding.

[Desert Rat]

I can tell you it would likely have nothing to do with the torsion bars. it does sound like you've gone through everything. All I can suggest is bleeding the system again.

[seang]

About that proportioning valve, what I mean is the NLSV (nissan load sensing valve), on the frame rail of, what I thought was all D21's. You sound like you know what is going on, I just wanted to get that out there.

sticking or messed up caliper

When you instaled the new calipers, did you use the old guide pins? These little guys are problematic if they aren't serviced thoroughly and frequently.

By thorough I mean: cleaning the pins with a wire wheel or wire brush; cleaning the guide bores in a similar fashion with something that will fit in there; and having intact dust boots. I use only synthetic caliper lube on them (costs only a few bucks), it seems to hold its ground longer than axle grease. -SeanG-

[kennybro]

Yep... the new calipers came with the hangers and all new hardware and I grease everything that should be greased, as far as the NLSV. I've been under this truck so many times looking for a "proportioning valve" and never found anything like it. Going to look later... again :-/
Thanx again to everybody for the ideas