What to look for when buying a Savana/Express AWD?

[wjeeper]

Would those 5160s be long enough after a 2" Traxda torsion bar lift?

The thing to keep in mind with a torsion lift is that you are just re-indexing the stock suspension to sit at a taller ride height. The shocks only need to be a bit longer. If you add too much droop the upper ball joints go bind and shortly after the tie rods at the steering knuckles binds up. Its better to max out a shock absorber before a critical steering related part. These shocks are 1" longer which means an additional 1.5 at the wheels.

I put a set on a buddies van and he had a 2-2.5 torsion key lift! and he really loves them. It helped firm up the front and it stiffened up the front end enough that you can run without the swaybars. This really loosens up the front end on washboards and lets both sides work independently of each other. The biggest benefit is the remote resivior, these shocks are so short that the oil tends cavitate and create shock fade pretty fast. The added oil and nitrogen volume allows the shock to do their job and stay cooler as an added bonus.

Now whey you first look at the specs of this shock it will look wrong. It is listed as having .5" less travel than the stock shock. and a compressed length that is longer than stock. This would mean the shock will bottom out before hitting the bumpstops. However the compressed length listed does not take into consideration the built in bump stop on the the shock shaft. We cut off the shock bump stop and installed some Z71 bumps from a 99-06 Silverado onto the frame. One thing to keep in mind with these vans is that the stock bump stops are actually designed to work with the torsion bars to provide a progressive compression rate to the torsion bars. I run the same shock (just a bit longer, I am sitting 5" above stock with drop brackets) and I love the ride quality!

The Bilstien part is 25-176407

 

[akskiffer]

The thing to keep in mind with a torsion lift is that you are just re-indexing the stock suspension to sit at a taller ride height. The shocks only need to be a bit longer. If you add too much droop the upper ball joints go bind and shortly after the tie rods at the steering knuckles binds up. Its better to max out a shock absorber before a critical steering related part. These shocks are 1" longer which means an additional 1.5 at the wheels.

I put a set on a buddies van and he had a 2-2.5 torsion key lift! and he really loves them. It helped firm up the front and it stiffened up the front end enough that you can run without the swaybars. This really loosens up the front end on washboards and lets both sides work independently of each other. The biggest benefit is the remote resivior, these shocks are so short that the oil tends cavitate and create shock fade pretty fast. The added oil and nitrogen volume allows the shock to do their job and stay cooler as an added bonus.

Now whey you first look at the specs of this shock it will look wrong. It is listed as having .5" less travel than the stock shock. and a compressed length that is longer than stock. This would mean the shock will bottom out before hitting the bumpstops. However the compressed length listed does not take into consideration the built in bump stop on the the shock shaft. We cut off the shock bump stop and installed some Z71 bumps from a 99-06 Silverado onto the frame. One thing to keep in mind with these vans is that the stock bump stops are actually designed to work with the torsion bars to provide a progressive compression rate to the torsion bars. I run the same shock (just a bit longer, I am sitting 5" above stock with drop brackets) and I love the ride quality!

The Bilstien part is 25-176407

Hi wjeeper
What is the difference from stock to Z-71 bump stops?

Regarding cranking the key. I have no idea if mine have been adjusted and wonder how their setup would be approached. Do keys preload the torsion bar or position the geometry?
My key adjusters have 3/8" left. What lift does this amount to? Anyone reading me will see I don't fully understand suspension dynamics.

 

[FlipperFla]

blanksky, we bought ours at 57k and are at 79k now. When we bought it, the front left wheel bearing was getting ready to fail. Symptoms were ABS kicking in during the test drive under moderate braking but not so hard as to lock up the wheels, the wheel also had noticeable play when it was off the ground and we tilted it from top to bottom. the replacement for this was not too bad, maybe 200~300$ (cannot remember clearly) since it included the ABS sensor.

The shocks were also quite worn out, it was not that evident with an empty van but once we added normal camper van weight the back would pogo up and down on bumps noticeably. I upgraded these as well as the rear springs and the front torsion keys.

We have no leak at our transfer case but there is a slow leak on the front differential, I record how much I need to top off at each oil change interval, it normally only 100ml or so but I think it is a somewhat common problem.

Rust under ours was moderate and made the suspension work a bit of a nightmare.

we are coming up on a spark plug replacement interval, either 80 or 90k which i hear is a pain in the butt, so keep that in mind depending on the mileage.

good luck![/QUOTE For some reason I seem to get corrosion on the contacts in the distributor cap and rotor, maybe from rain being funneled into the engine compartment, about every 25k miles I clean them, if it misfires it will trigger the check engine light. To change the front plugs you go through the wheel wells. Changed all my oils to synthetic. Never had any major issues with 180k miles.

 

[wjeeper]

Hi wjeeper
What is the difference from stock to Z-71 bump stops?

Regarding cranking the key. I have no idea if mine have been adjusted and wonder how their setup would be approached. Do keys preload the torsion bar or position the geometry?
My key adjusters have 3/8" left. What lift does this amount to? Anyone reading me will see I don't fully understand suspension dynamics.

The z-71 bumpstop is taller and is a bit firmer. The extra height helps offset the height gained from cranking. The bumpstop should be just touching the control arm at ride height. Go with ACDELCO bumps, the doorman units just don't last in my experience, plus the ACDELCO ones are only like $20 ea anyways

Timbren has the GMFK25s front bump stops I really want to try but they are well over $200. Sumo springs has a kit out there too......but the OEM Z71 bumps are cheap and work great.

With torsion bar keys or cranking you shouldn't be pre-loading the bar. If your pre-load the torsion spring your probably maxing out against the droop stops like the video below.

3/8" worth of adjuster thread should get you (totally shooting from the hip here) 1"+ There is lots of Strait up bad and misleading info on chevy fourms about torsion suspensions, toyota guys seem to have a better grasp on how they really work. Norcal nick has a good primer on torsion front ends, he is discusing Duramax 2500's but the parts are super similar between them and our vans.

https://www.duramaxforum.com/forum/...nito-leveling-kit-packages.html#/topics/13997