Topic: Avoiding bump steer

[neale_rs]

Assuming a 4" lift on a YJ, which of these setups do you think would best avoid bump steer?

1) Stock setup.

2) Track bar relocation bracket, no drop pitman arm.

3) Track bar relocation bracket, with drop pitman arm.

4) Remove track bar, use drop pitman arm.

Thanks

[Jeffy]

Assuming a 4" lift on a YJ, which of these setups do you think would best avoid bump steer?

1) Stock setup.

2) Track bar relocation bracket, no drop pitman arm.

3) Track bar relocation bracket, with drop pitman arm.

4) Remove track bar, use drop pitman arm.

Thanks

Well, here's the deal.  The drag link and the trackbar need to be in the same plane.  That means change one and you have to change the other or else it will bind.

Depending on how stiff or soft the leafs are you will either have very little bumpsteer (hard) or some bumpsteer (soft).  This has to do with the suspension compressing.  When teh suspension compresses the distance between the axle and the steering box is reduced.  Since the drag link is a fixed size it will force the tires to turn.  When the suspension rebounds it it will pull the other way.  This is why you will feel a tug in the wheel.

The best way to get rid of bumpsteer is to have your drag link parallel to the ground.  This way the change isn't so drastic.

With that said, I have a SOA, no trackbars and a dropped pitman arm.

[neale_rs]

It sounds like no track bar and a dropped pitman arm would work well.  Based on what you wrote, it seems that the best setup would be a dropped pitman arm and a track bar relocation at the frame to keep it lined up with the drag link.

Thanks

[Jeffy]

It sounds like no track bar and a dropped pitman arm would work well.  Based on what you wrote, it seems that the best setup would be a dropped pitman arm and a track bar relocation at the frame to keep it lined up with the drag link.

Thanks

I wouldn't say it's the best.  I get a lot of bumpsteer but I'm just used to it.  My Jeep will pull hard when braking hard.  It's severe enough to pull you into the next lane if you're not paying attention.

The best solution is a hi-steering setup.  I guess second best would be a dropped pitman arm and a trackbar.  That's for onroad though.  For offroad, you won't notice bumpsteer very much since you're not going fast enough for it to pull.  While offroad, you won't want to have the trackbar either.

The reason I removed my front trackbar was that with the extension, it would never stay tight.  After a while the bolt would loosen up and it would *clunk* every time the suspension moved.  I got tired of listening to the clunk so I removed it.  Now it's been replaced by the clunk of my swaybar disconencts since the suspension is able to move.

[neale_rs]

I better be careful then.   In any case, it seems the drop pitman arm is a better bet than the stock one.

I had a brake problem for a few months that would pull me into oncoming traffic.  After a while the steering compensation became automatic and once the problem was solved I would swerve a bit to the right when braking until I got used to the new brakes!

[jfrabat]

It sounds like no track bar and a dropped pitman arm would work well.  Based on what you wrote, it seems that the best setup would be a dropped pitman arm and a track bar relocation at the frame to keep it lined up with the drag link.

I'm currently runing a RE 4" lift with a dropped pitman and the trackbar (with the relocation bracket at the axle) and I have not yet felt any bumpsteer.  I do know the trackbar is not allowing the suspension to compress fully, but since I am driving the Jeep onroad only (for now), I am leaving it in place.  When I take the Jeep offroad, I plan to take the trackbar out.

By the way, I will have swaybar disconnects, but since I screwed up the threads of the special bolts that tie the sway bar to the links (or in my case, the swaybar disco's), I am currently running without the swaybar (that will change as soon as the stealership gets the bolts I paid for about 2 months ago in and I can put the discos back on!).

Felipe

[neale_rs]

It sounds like no track bar and a dropped pitman arm would work well.  Based on what you wrote, it seems that the best setup would be a dropped pitman arm and a track bar relocation at the frame to keep it lined up with the drag link.

I'm currently runing a RE 4" lift with a dropped pitman and the trackbar (with the relocation bracket at the axle) and I have not yet felt any bumpsteer.  I do know the trackbar is not allowing the suspension to compress fully, but since I am driving the Jeep onroad only (for now), I am leaving it in place.  When I take the Jeep offroad, I plan to take the trackbar out.

By the way, I will have swaybar disconnects, but since I screwed up the threads of the special bolts that tie the sway bar to the links (or in my case, the swaybar disco's), I am currently running without the swaybar (that will change as soon as the stealership gets the bolts I paid for about 2 months ago in and I can put the discos back on!).

Felipe

Great info, in fact I'm strongly considering getting that same lift.  How is the on-road ride? Thanks

[jfrabat]

I am actually very happy with this set up.  The ride is now a bit stiffer than it was before the lift (but hey, first, the suspension in my rig was about 14 years old, and, secondly, it IS a Jeep, not a Camry!  The best way i can describe it is that it now rides like a pickup truck; that should let you know about how stiff it is), but not so much so.

I did buy a dropped pitman arm, and have that installed.  I also had to reverse the rear shocks, as otherwise they would rub on the axle, and I ran into some problems installing the brake lines (I ended up having that done because I was ruining the nuts; that's how stiff they were!).  Also keep in mind that if you install a CV shaft (I also installed the SYE and driveshaft at the same time), you will need to rotate the rear axle so that the pinion is in line with the shaft.  This involves taking the old spring perches of the axle, installing the axle and new perches to get the angle right, tack welding the new perches in place, taking out the axle, welding the perches all the way in, and reinstalling the axle (I have no welding equipment, so I had this done as well).  If you do not do this, you WILL have STRONG vibrations!  Of course, you can always install a TC drop kit (included) and the wedges for the axles (also included).

[neale_rs]

I like how pickups ride so that's pretty good.  My setup is a bit different because my rear shocks are mounted on u-bolt skid plates, placing them farther from the axle.  Also my axle is already rotated (not the best setup for an unlifted jeep but it has no vibes anyway) in anticipation of a lift (was done when the D44 was swapped in).  The RE4 sounds like a very good lift.  I still can't decide between this lift and an OME 2.5" lift.  I'll probably end up with the RE4 to end the temptation to lift it more later.

[jfrabat]

I like how pickups ride so that's pretty good.  My setup is a bit different because my rear shocks are mounted on u-bolt skid plates, placing them farther from the axle.  Also my axle is already rotated (not the best setup for an unlifted jeep but it has no vibes anyway) in anticipation of a lift (was done when the D44 was swapped in).  The RE4 sounds like a very good lift.  I still can't decide between this lift and an OME 2.5" lift.  I'll probably end up with the RE4 to end the temptation to lift it more later.

2 things; if you are even considering 4", go with the 4" lift (regardless of the brand).  Many people buy a small lift only to change it later on for a larger lift.  Figure out what you want to do with your rig, then figure what size of tires you will need, and base your decision on that.  Invest only once on suspension and save the money for other mods!

Also, the rotation of the axle will depend on the position of the axle after the installation, so you may still need to modify it...  Just keep that in mind so that in case you actually need to do it, it will not come as a surprise.

Felipe

[neale_rs]

Yeah, saving money is what I need to do!  Thanks for the tips.

[97 TJ - I dont wave]

I bought Rusty's dragling link and tie rod and a drop pitman arm with my 4 in procomp lift. Best steering MOD I made. Steer's tight with almost no bump steer/drifting....
97 tj