JKOwners Forum banner

Alignment help

4K views 32 replies 11 participants last post by  rlee 
#1 ·
Hello fellas. Couple of questions here, but first a quick run down of what I've got. I bought my newest JKU in 2018. I had a local shop weld on the EVO long arm kit (with high clearance brackets in the rear). I swapped my Dana UD60s, shocks, steering setup (Currie links and WTO hydro assist), tracbar, bump stops, etc over from my prior Jeep (an 07 JKU). Ever since the day we finished it up it has pulled to the right. I've had it at two different alignment shops and I've messed with it a ton (plumb bobs, tape measures, angle finders, rotating tires etc). I cannot get it to drive without the pull. My last Jeep with all of the same parts (actually had the same EVO arm kit welded on as well) drove perfectly straight. Sorry, I don't have alignment spec sheets to show. I've been around alignment shops for many years and know how to read the sheets, and from what I saw it was perfect after we aligned it. One of the shops is specifically an alignment shop (Alignment Specialties) here in St Louis. The dude knows his stuff and he is stumped as well. From the readouts it should drive straight.

On to the questions:

1) Has anyone had a pull or push from a hydro assist? I've had mine on stands and checked it while idling and revving it up. The front tires didn't move. Alignment Specialties said to check this.

2) My TB and draglink are real close to being parallel but are off just a bit. With an angle finder they differ about 1 degree. The TB read 7 degrees and the draglink read 6, so a degree off. Would this make it pull. I've read many times this can cause bump steer. I wouldn't say I have a lot of bump steer.

3) I just noticed tonight, right before I sat down to write this, that the two end joints on the draglink are not in alignment. The end at the pitman arm sits fairly straight, or level, and the end at the knuckle is turned slightly. Maybe it's putting a force on the knuckle making it want to turn out a bit but I couldn't imagine so. The steering wheel is straight. Thoughts? I'll check this tonight or later this week.

4) When I took it into get my first alignment the shop adjusted the thrust angle from where I set it originally (when we set the rear arms up we made them the same length for driver and pass sides. After that alignment, and it was still pulling to the right, I put it back to where I thought it was straight (using the plumb bobs and tape measure method). It still pulled. After getting tired of it again I took it to the specialty shop. He moved the axle also making the thrust angle come back into spec and it matched the first shops setup. I believe I know the answer here, but what if I added some thrust angle to help it pull left. I don't want a vehicle that doglegs down the street though lol. Thoughts?

I'm lost and after dealing with two shops it's getting very old. I've looked at everything from ball joints to warn tires, tire pressure, loose end joints on the links. Everything is tight. Help please!!
 
See less See more
#2 · (Edited)
One more thing. When I am working on the Jeep, specifically the front, to droop the passenger side wheel I have to use a jack to raise the driver's side. It seems that it binds or just won't go over center to fully droop the pass side. Or in other words lets say I want to remove the pass side coil spring. I'll let the axle droop all the down (tires removed). It doesn't fully droop. The shocks are at least 4" from maxing out. If I raise the driver's side the pass side will droop then allowing me enough to max out the shock or even more to remove the spring. Is this because of a poorly setup system on the front or is this common for a four link with TB? I don't remember if my last Jeep did this or not. I've never noticed it being a problem off road. Usually the drivers side is on a rock or ledge in those cases helping push the pass side down. Thoughts?

Edit: forgot to say that this is with the sway bar disconnected.
 
#3 · (Edited)
. . .

On to the questions:

1) Has anyone had a pull or push from a hydro assist?
I haven't. A single-ended ram will have more force potential on extension due to piston area not reduced by rod cross section, but you'd have to pressurize both sides to make it drift. A damaged steering box could possibly give the ram that potential, but my tapped stock box with PSC pump & a good filter & cooler doesn't do that on my setup.

2) My TB and draglink are real close to being parallel but are off just a bit. With an angle finder they differ about 1 degree.
Did you use your angle finder on sections that are inline with their end joints?
If not pull strings from joint to joint on each and eyeball them from the front.
Better yet, do that and take some pictures :bounce:

3) I just noticed tonight, right before I sat down to write this, that the two end joints on the draglink are not in alignment. The end at the pitman arm sits fairly straight, or level, and the end at the knuckle is turned slightly.
That's so your drag link won't droop down and look funky.
Unless the joints are binding (clocked too far) there is no down-side to doing this.

Maybe it's putting a force on the knuckle making it want to turn out a bit . . .
No.

4) When I took it into get my first alignment the shop adjusted the thrust angle from where I set it originally (when we set the rear arms up we made them the same length for driver and pass sides. After that alignment, and it was still pulling to the right, I put it back to where I thought it was straight (using the plumb bobs and tape measure method). It still pulled. After getting tired of it again I took it to the specialty shop. He moved the axle also making the thrust angle come back into spec and it matched the first shops setup. I believe I know the answer here, but what if I added some thrust angle to help it pull left. I don't want a vehicle that doglegs down the street though lol. Thoughts?
It could work, but I'd rather understand what I'm correcting for before jacking scoliosis into the running gear.
Once you know why . . . sure, why not? :laughing:

I'm lost and after dealing with two shops it's getting very old. I've looked at everything from ball joints to warn tires, tire pressure, loose end joints on the links. Everything is tight. Help please!!
See above, and add some freakin' pictures already :cwm13:

One more thing. When I am working on the Jeep, specifically the front, to droop the passenger side wheel I have to use a jack to raise the driver's side. It seems that it binds or just won't go over center to fully droop the pass side. Or in other words lets say I want to remove the pass side coil spring. I'll let the axle droop all the down (tires removed). It doesn't fully droop. The shocks are at least 4" from maxing out. If I raise the driver's side the pass side will droop then allowing me enough to max out the shock or even more to remove the spring. Is this because of a poorly setup system on the front or is this common for a four link with TB? I don't remember if my last Jeep did this or not. I've never noticed it being a problem off road. Usually the drivers side is on a rock or ledge in those cases helping push the pass side down. Thoughts?

Edit: forgot to say that this is with the sway bar disconnected.
Sounds like your track bar is limiting your droop unless you have a center limiting strap, or arm joint(s) binding? :dunno:

Need photos to make guesses more educated. "Can't smell anything over the phone" :thefinger:
 
#4 ·
You might be able to disconnect the pitman arm and start the engine to determine if the problem is geometry or hydraulics.... maybe?

If the pitman arm turns on it's own, it's likely the steering box. If the drag link moves on it's own it's likely the steer cylinder. If neither, then likely it's something either binding, or in the geometry. Feel free to check my thinking, but that sounds like a good diagnosis plan in my head.

Good luck.
 
#6 ·
I used to use PhotoSuckit, but went scorched-earth on them in response to their extortion attempt.

Now I just upload to my JKO threads, but that requires a star (paid subscription) - personal choice, not needed.

I've had good luck using Postimage.org --> https://postimages.org/ for images on websites where I don't have upload ability.

Free and, at least so far, everything I've hosted there is still working :beer:
 
#11 ·
Running about 4" lift. The trac bar has a raised mount which is at about 3".

Fellas. Last night I measured my rear axle off of 3 spots on the frame to see if it looks like it is sitting straight (perpendicular to the frame). It seems to be almost spot on. With that being said the pass side pull has to be in the front steering/axle setup.
 
#15 ·
Try swapping your front tires side to side to see if that affects anything. Also have your double checked that your rear control arms are set to the same length, i.e. is your rear axle cocked one way or another? It may be that the control arm brackets were not welded on in the correct positions since that seems to be one of the major changes.
 
#17 ·
How does my setup look? The draglink and TB are not exactly parallel, not too far off but not exact. Does this affect steering or droop on either side? And, at 4" lift, are my angles too steep? Should I raise the TB and do a drag link flip?
 
#18 ·
The draglink and TB, ideally, should be parallel, but being slightly off is not too big of a deal.

When they are not exactly parallel, it induces what is called "bump steer". It's called this because when you hit a bump and compress/decompress the suspension, the draglink and TB move in slightly different arcs. Because the TB is fixed on both ends, the geometry causes the draglink to be moved to keep pace with the slightly different TB arc. This induces some steering input.

To make a long story short, when the draglink and TB are not parallel, it can cause the steering to move a bit when you hit bump.

I would not expect it to affect droop in any way.
 
#20 ·
If you hold the steering wheel centered it goes down the road straight? The you let go and the vehicle pulls and the wheel starts to turn in the direction of the pull? How about if your coasting? Have you tried a set of stock tires?
Did you get a alignment printout with you front and rear toe/camber?
 
#21 ·
If you hold the steering wheel centered it goes down the road straight? YES, BUT WHEELL IS HELD SLIGHTLY LEFT OF CENTER The you let go and the vehicle pulls and the wheel starts to turn in the direction of the pull?YES How about if your coasting?YES, STILL PULLS Have you tried a set of stock tires?NOT YET. I'LL HAVE TO SEE IF I CAN GET MY HANDS ON SOME 8 LUG TRUCK WHEELS
Did you get a alignment printout with you front and rear toe/camber?YES BUT THEY ARE GONE
Thanks. See answers in red.
 
#22 ·
People think they are a suspension pro because they have done a alignment. The basic measurements you get, even when you include thrust angles and SAI are really the start of something deeper.
I was working for Dodge in 1994 when the new Ram came out and we had a rash of pulling problems. Dodge put a team of engineers to solve the problems and they generated a off site course to train their seasoned Tech's. The point is that sometimes it can be complicated.
If it were my Jeep. I would go back to where you had it aligned and get them to print another alignment result. It is stored in their machine and only a couple mouse clicks to print it. Make sure you have all the measurements. They original probably gave you a sheet with camber/toe/caster. But get them to print another with all the axle setbacks and track measurements. If you have to pay for a alignment check to get this then do it. Then I would find some stock sized wheels to try.
Then if your measurement look okay I would find a shop or someone I could send my information to who specializes in autocross or road races. Us Jeep guys put up with a lot just to go off road but a proper road race shop is more experienced at the whole package.
I worked for a guy years ago and we would heat and bend toe into solid axles on race cars, something the Jeep world thinks is blasphemous.
 
#24 · (Edited)



These threads always seem like you're trying to hunt squirrel by using someone's typing to find/aim/shoot the thing.

the two photos help but maybe it's an arm or pitman or rear issue .

throw us some more picts of the suspension bracketry & steering gear ,etc while it's up on that rack


edit: I thought that over 3" - 3.5" of lift it is advisable to flip the draglink.
 
#25 ·
my Jeep pulled to the right before too. i resolved it by adding more caster to the side its pulling (right side) knowing that the thrust angle, toe and caster are within specs. i did this by extending the right LCA, and shortening the left UCA. Did this a little at a time till the pulling went away so i dont have any hard numbers to give you. But it was about give or take a full turn on my Synergy control arms
 
#29 ·
Your rear axle is sitting a little bit off. If you have adjustable control arms straighten it out. Not a problem just a little ocd on my part.
You don't have any caster spread on the front. I set a IFS truck with .5 less on the drivers to compensate for road crown. You may end up having to install some offset ball joints.
 
#30 ·
How would you add .5 degrees on pass or remove drivers? Someone mentioned in an earlier post lengthen pass lower shorten drivers upper. Or would you push the pass side forward with upper and lower? Or other? To me, I would want to add to pass upper and extend driver's lower. Or am I thinking backwards?

My rears are adjustable so that's no problem.
 
#31 ·
Couple thoughts:

Road crown does induce a Rightward pull if everything is straight on your alignment. You may need to lengthen your R lower front arm and shorten your L lower front arm a hair.

Also,

Have you checked and verified wheel bearings are good, brakes are not dragging, ball joints turn smoothly without play.
 
#32 ·
You can't change the caster spread on a solid axle with control arms. The axle tubes would have to twist in the housing. If you lengthen and shorten the control arms you would preload your bushings and change the caster on both sides equally. You would just end up with premature wear on the bushings. Offset upper ball joints are the easiest.
 
#33 ·
Your caster is at 4.6/4.8. lengthen the lowers to see if it helps the pull. IDK if your DS u-joints can handle more caster but give it a try even if you have to pull the DS for testing. I don't have as much lift but my Jeep works best at 6.5 caster.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top