I use to race (road courses) trucks with torsion bar front suspensions. In regards to wear on the torsion bars, change of ride height will make no difference because the same stressors are still in effect in a consistant manner- meaning the loading has not changed (unless you plan on bottoming out the suspension on a routine basis, which would only induce increased rotational flex on a raised vehicle).

With regards to adjusting, the vehicle should be position with all wheels on the ground, on a level surface. The bars should be adjusted at 1/4 turn alternating between each torsion bar to ensure the equal raising/loading of the vehicle, measuring the amount of raise every 3/4-1 rotational adjustment. Then if the vehicle is raising unequally, you can make fine adjustments.

With a typical 1-2" ride adjustment, that is still within the operational range of the CV joints so the impact should be minimal.

 

If you don't take the pressure off of those little bolts before you crank on them, your likely to snap them off. I guess you got lucky.

 

i have never broken an adjuster and i leave the truck on the ground and measure both sides till done. if you broke a bolt, then it must have been rusted in the hole to start with. the bolt heads are probably 18mm, that makes the bolts probably 13 mm or close to 1/2 inch, but they are metric. you may or may not need the front end aligned. cranking will make the tires tip out slightly at the top. it may or may not still be in spec, depending on where it was to start with.

 

My driver side rear has always sagged a bit. It has four wheel air suspension. I had read that this sag was a feature built into the air system to allow the truck to 'kneel down' for shorter/women drivers to have an easier time of getting into the truck (which always sounded like a bunch of bs to me). I took it to a dealer in 2000 and that's what they told me and that it was normal. Now I am thinking (8 yrs later) that I should try tightening the left torsion bar to see if it levels out. Can I do this to just one side?

 

Definatly jack the truck up before you do it. It takes alot of stress off it and will make it easier for you. I dont know about the whole sagging issue. Mines been cranked for 3+ years and still the same.
You will get extra wear on your cv's though, and you will have a little rougher ride. If you go to a parts store with lifetime warranty on CV's, that will resolve that issue.
And if you do crank them, crank em all the way and then back off 1 turn.
And yes, you do both sides the same.

 

ya my ride was soooo stiff
but i beat the **** out of my truck on a regular basis

 

Cranking torsion bars doesn't change the spring rate so the ride should be the same. However...doing this reduces the downward travel available. (droop, if you will) Hitting a pothole or something can make the truck hit the limit stop on the downward travel stroke and create the sensation of a stiffer, less compliant ride.

It's a great mod for appearance and increase approach angle if you go off-road. But you lose downward articulation in the same amount you lift it.

 

You wont have torsion bars, you have inflatable air bags at all 4 corners.

 

Nope, been under the truck for various repairs over 8 years and see the two torsion bars every time. I see the adjusting bolts, I'm just wondering if I can adjust one side sligthly to get it level (?)

 

I was under the impression that the 4 wheel air suspension was similar to the navigators suspension. Which only has air bags, no other kind of springs.
I guess expeditions use a different setup then.

 

he probably has air helpers front and rear. a true air susp wont have torsion bars

 

It has four wheel air suspension and it has two torsion bars. Trust me, I just replaced a whole bunch of bushings and ball joints on the front and had to unload the tension on those bars to do some of the lower control arm bushings. When I torqued up the bars after the work to the same marks, it still had a slight lean to the left, not bad, maybe an inch. So my question is; can I adjust just one side slightly to get it level? Or is that a bad idea? I guess I could replace the rear air spring bags due to age, but the are not really leaking right now, so I am thinking a slight tweak to just one side's torsion bar might do it. ??

 

sorry just read it is exp not f150. thats what was confusing me. my bad should have read better

 

you can crank one torsion bar to make it level. it shouldnt hurt anything.

 

No prob, I appreciate your knowledge and help and it keeps me in check. I thought it was a weird set up under the expy, too, first truck I've ever had with torsion bars. Only other time I saw it was on a modified Humvee we rigged up in Iraq to up-armor it, one of my guys put in two torsion bars in it but they were criss-crossed, and me and another specwar brother welded the plates over it on the frame. It definitely made the rig stiff, but safe. Anyway, thanks for your help.