Lifted K10 steering pull

[1970Chevrolet]

Hey guys, I just picked up a new 1977 K10 this weekend that's sitting on 40s. I love this truck already. Drives pretty great. But there is one steering issue I'm a little concerned with. When I'm at highway speeds it drives straight even over bumps which is awesome, but if I start to turn it feels like it wants to pull that direction harder than it should. I noticed this first when I was taking it for a test drive when I went to pick it up. I kind of rocked the steering wheel left - right - left - right to feel how much play there was (not much) and it put the truck in a bit of a wobble to where I had to try and regain control because it kept wanting to pull kinda hard in each direction. Does anyone know what could be causing this and if there's anything I can do to reduce that pull? Here are some pics of the truck since everyone likes pictures...

[mongocanfly]

Truck is a bueat...
If its not a alignment issue then i think the issues your having could be related to the lift, it could have the steering geometry out of kilter...crossover steering may help/solve the issue....I've got this setup going on my truck.....you'll have to change to a 2wd steering box and depending on your knuckle design change the pass side knuckle....and ad the crossover draglink...These guys were really helpful.....
http://offroaddesign.com/catalog/Dana44crossover.htm

[kwmech]

Need pics of the front end and related steering components, pinion angle etc

[RADustin]

sounds like not enough caster to naturally straighten out the wheels.

sometimes wedges are installed in the front axle to make the pinion angle better match the driveshaft angle.

When this is done it reduces caster unless the inner c's are cut off and clocked.

[1970Chevrolet]

Thanks guys, I will get some pictures of the front suspension and post them later.

[obijuan]

In picture 2 you can see the diff cover pretty dang close to flat. Caster is probably pretty close to good. I'm betting toe was not adjusted when bigger tires were put on. Sounds like it might just needs to be toed in.

[1970Chevrolet]

Here's a couple pictures. My phone camera sucks apparently. That's as good as I could get.

[obijuan]

Let's not ignore that you need a drop pitman arm. You have your caster shims in place so I doubt that's a major contributor. That tie rod adjuster sleeve doesn't have any tool marks on it. Get that drop pitman arm on it and realign it.

[abig84]

Frozen u-joints in the wheel joints will cause similar issues. Easy way to check is lock one hub, turn the wheel and Jack it up and try to spin it. If it doesn't move freely then they are bad

[1970Chevrolet]

Awesome, thanks guys. I'll try these suggestions.

[mongocanfly]

Even if this isn't causing your issue it's not good....

[Ski-me]

With that much lift to run 40's I'd suggest the crossover steering too.

The top red line should be more horizontal if set up correctly. Drop pitman and/or raised steering arm. After all that, it's not going to be the best.

Investigate crossover at ORD.

Probably check your ball joints and steering linkage at the same time. 40's aren't going to be forgiving on all that 1/2 ton equipment.....