Ok, Tim vs the alignment, where to start

[mysticclam]

Ever since my 2 inch skyjacker lift and 33s, my truck has not driven well. I didnt expect it to be as good as before but once you get to speed you are constantly fighting to keep it in a straight line. It will pull to one side for awhile then suddenly pull hard the other way. Anything above 55 is too scary. Ive had it to Les Schwab a bunch of times and it never gets right. Ball joints and Wheel bearings are good according to them. Everything was in spec except for cross camber. That was a while ago but not many miles ago. I have tried a completly different set of tires and get the same exact thing. I measured some stuff today and the distance between the front and rear wheel center is longer by about 1.25 inches on the passenger side. Also, it seems to be toe-out by about 5/8 inch. I cant measure caster but it is visibly positive. It drove straight before I did the lift. Also, I have the oversized Camber Bushings in for the camber. I beleive they are 2.75 degrees. Im going to look for play in the tire rod ends. Also, one shop told me the drag link was worn where it connects to the pitman arm and when I took it to another shop near work to get it replaced, they said it was fine and didnt replace it. Im thinking of just replacing it to see if it helps. Maybe the tire rod ends too. Is the drag link supped to have a slight bend at one end?

 

[dogfriend]

Holy crap, I'm no alignment expert, but 1.25 inches difference in wheelbase from side to side sounds huge. Can you tell if the rear axle is perpendicular to the frame?

Find a spot at the center of the frame rails near the front, then measure from that spot to each rear axle flange (or the same point on each side of the rear axle) The measurement should be the same.

If it isn't, try to correct that first, then align the front.

 

[Tbars4]

this is why i try to talk people into doing the f150 coil spacers as they are only 1 1/2" and that is a big difference...i'm not all familiar with the 2" lift kit but it sounds like you need to get the 4" axle drop brackets to get that camber back in line...they will drop your axles about 2"'s and then you will have to get it realigned...i just did the steering rack and to see if you need a new draglink, start your truck up and have someone shimmy the steering wheel real quick...you will know right away if that needs replacing...here is a link to my steering parts thread....good luck...
http://www.explorerforum.com/forums/showthread.php?t=189668

 

[mysticclam]

I didnt do the spacers because my stock springs were already sagging. What about the toe, shouldnt it be toe in like an 1/8 inch not toe out?

Also, my camber is in spec and it pretty close on both wheels. The caster is in spec but one wheel is at one end of the range and the other is at the other end. So That makes the cross caster out of the acceptable range.

 

[Tbars4]

exactly, and it's your passenger side that is the main problem??? as for the toe, i string line mine from the center of the rear wheel to the front of the front tire....where it touches the front tire, in front, mine is usually a 1/4" out past the rear tire...if i were to bring it in i would get the shimmy on mine between 40-45 mph...i would say no more than that but my truck has 35's with a 6" lift...and i'm not an alignment guy, just a guy that does some aligning between alignments...

 

[410Fortune]

1/4" toe out total is fine, 5/8 per side is not

Try adjusting your tie rods yourself to get to the 1/4" toe out

If your camber is then 0 degrees or slightly + it should track straight and you should not have to struggle

You should consider a 2" drop pitman arm

 

[Tbars4]

410, fortune, thanks as i've been wondering what the relm of it was...i know mine is really good at 1/8" - 1/4" and thats it...and good point on the drop pitman...i'm not sure what that 2" lift includes at all and if i remember, alot of companies don't supply the pitman, but it is usually a side note...

 

[mercious]

if you have a big caster split also, that could be causing your pulling like that at the higher speeds cause caster mostly affects those kinds of speeds the most. the toe shouldnt be making it pull like that, will affect the tire wear mostly

 

[mysticclam]

If it was a consistent pull It would make more sense, it really pulls significantly hard one way about 80 percent of the time, then suddenly wont.

I went and measured the axle perches to a couple different points on the frame and got the exact same measurement for each side so i think we can rule out the rear axle not being square. I also had someone help me measure this time and found the front to rear wheel center measurements is only off a touch more than 1/2 inch from one side to the other. The top ball joint is an inch rearward of the bottom on both sides so the caster must be pretty close to the same.

I bet if I adjust the toe, the side to side will be more equal as basically when I have one wheel straight, the other would be turned a tiny bit which would move the center of the wheel back in relation to the other.

I think I may get the caster adjusting radius arm bushings. I can then adjust them to see what helps. I know they are weak but if I figure out its a caster problem, I can work from there. Also, they are fairly cheap and my rivets have already been replaced with bolts so it shouldn't be too hard to do.

How much camber difference will cause it to pull. Seems pretty close to equal. I may need to go to an alignment shop just to get a new printout as I cant find the old one.

 

[Tbars4]

talk about tire wear, when wasthe last time you rotated your tires and how new are they...

 

[mysticclam]

They are tires I got used. I have tried them in different positions and it makes no difference. I still have my 31s on the factory rims and the problem is identical with them on the truck so its not the wheels or tires.

Hey if I put 31s on just the back that would be a quick way to see what a bit more caster would do. Might try that.

 

[mercious]

a degree split will make it pull, but if you either have REALLY high caster or REALLY low caster it'll do the samething, make it wonder the road like that

 

[Tbars4]

here is a thread for you....
http://www.explorerforum.com/forums/showthread.php?t=187201

i don't know if you already read it but i'm sure the pics are more dramatized than what your tires are...i am thinking everything was fine with your truck but now it's not...as i mentioned before, i believe if you added some parts it will correct this problem...that is why i still suggest for people to do the f150 coil spacers as they are only 1 1/2" and that extra half inch threw you off...and as you stated before, one side is in spec, the other isn't...

 

[mysticclam]

Well, i didn't get back to this for awhile as our new daughter arrived. Finally got back to it and went ahead and put the 31s on the back. Truck still pulls to one side but its constant now. Doesnt do the wandering thing. Its simply a bit annoying as opposed to scary with the matching tires. Also, its easier to turn. So if the rear tires are 2 inches shorter, that is like a 1 inch drop of the frame at the rear axle. At the rear of the radius arm it would be hardly anything so Im sure now that adjustable radius arm bushings could fix this if worse comes to worse. I think Im going to go find someone who does non computer alignments and tell them exactly what its doing and that it needs more caster. Too bad there is no way to drop the radius arm bracket a 1/4 inch or so....

 

[Tbars4]

congrats on your new arrival...