Adjustable track bar for '03+

[Spooled-up]

I e-mailed DT profab today and asked:



Seems like a lot of members on the Turbodiesel Register are doing 2" spacers in the front to fit larger tires. I understand that this moves the axle 1/4" to the side. Do you have any plans to make an adjustable track bar for the '03+ year trucks?



The reply (which came within one hour)"



YES AND HOPEFULLY WITH IN THE NEXT COUPLE OF MONTHS

DAVE





Sweet.

 

[rbattelle]

I'd like to have an adjustable trac bar and a drop bracket for it. I believe this is the only way to achieve proper suspension system alignment.

 

[TBrennan]

Not according to T-Rex. If you read the well written piece from them, they're take is that your only aligning the thing for how it sits at rest and not through it's full articulation. An interesting read (search in the accessories forum). They lift the front a few inches but don't adjust the trackbar or bumpstops.

 

[Spooled-up]

Although I haven't read the article, it seems to me that my truck is almost always at rest (suspension wise) so this is where I would want it to be always in alignment.

 

[KevinWatts]

You wouldn't want a drop bracket because that would give you bump steer, but the adjustable arm would bring the axle back under the vehicle.



. 02

Kevin

 

[CIverson]

The argument by T-rex is that when your suspension bottoms out, they axle will not be aligned and could miss the bumpstops, or at least not hit them squarely.



I agree with that view myself, and if you want to adjust it to center w/ a 2" lift then you should lower the bumpstops accordingly.



Also, it's been awhile since I looked at the T-bar, but isn't it straight? If so an adj. one can be easily fabbed w/ some DOM tubing Heims and weld in thread thingies.

 

[rbattelle]

I guess when I said "aligned", I mean "maintain suspension geometry". In my opinion (and this is only my opinion... NOT fact), the only way to lift/level a vehicle and do it properly is to include a track bar drop bracket to bring front suspension geometry back into spec (except for the increased height, of course).



Again, this is my opinion.

 

[Blakers]

Shouldn't the track bar be parellel to the drag link? I think I read that somewhere.

 

[ThomasLawrence]

the only way to lift/level a vehicle and do it properly is to include a track bar drop bracket to bring front suspension geometry back into spec (except for the increased height, of course).

Yes, but only if a dropped pitman arm is used. If we assume the drag link and track bar swing in the same arc from the factory, then to maintain that geometry, you would need to lower the track bar the same amount as the drag link was lowered.



In practice, this isn't always doable, so therefore the trackbar is lengthened, as well. This keeps the axle centered at ride height, but introduces a (usually small-to-imperceptible) amount of bumpsteer. For example, on my '99, I measured my drag link at 32", my DT track bar at approximately 36" (going from memory here), which translated to about 2° of bumpsteer throughout the movement of the axle. That's not bad, and isn't noticable to me while driving the truck. Other setups produce far worse results.

Shouldn't the track bar be parellel to the drag link? I think I read that somewhere.

Yes, if possible. The reason is that you want the drag link and track bar to swing in the same arc as the suspension cycles. This keeps the distance between the pitman arm that the end of the drag link (where it exerts force on the steering) the same. When they don't swing in the same arc, you have the axle moving side-to-side. Since the drag link can't stretch or compress (a good thing ), something has to give. Either the steering wheel remains steady and the tires turn, or the tires remain pointed in the same direction and the steering wheel turns. It depends on how tightly you're holding on at the time.



-Tom

 

[JHardwick]

whoa whoa whoa, this is not an IFS.



I haven't studied my front end, but I think you are making this more complicated than it should be.



I just got home @ 9PM, but i'll look at it tomorrow and get back ... ... ... ..... hold that thought, LOL.

 

[ThomasLawrence]

whoa whoa whoa, this is not an IFS.

Right... that's why there's a track bar

I haven't studied my front end, but I think you are making this more complicated than it should be.

It may look simple, but there's a lot of thought that goes into the design of any suspension system. True - a drag link is a pretty simple piece - just a stick that connects the steering knuckle to the pitman arm. A track bar is also simple - a stick that connects the axle to the frame, preventing side-to-side movement. The interaction between the two, well... that's what we're talking about

 

[lndscpe]

Solution? Well, what is the solution to raising the front end a couple of inches? Is the change in geometry noticable when driving? what deterent is there in adding a leveling kit to the front end of our 3g's? Any insight would be appreciated as I'm considering this as an option on my 3500.

 

[CIverson]

The only downside to just adding a leveling kit and nothing else to the suspension, is the axle shifts towards the drivers side a little bit. Like 1/2" I think. There really aren't any other drawbacks geometry wise as long as you get it realigned.



I can't even tell mine shifted, I never look at it that closely.

 

[JHardwick]

Originally posted by ThomasLawrence

Right... that's why there's a track bar

A track bar is needed in a coil setup regardless of IFS or not.



At a quick glance this morning, here is exactly what I would do if I raised my truck 2".



I'd pull the pitman arm off and bend a 2" drop in it. I'd add a little twist too, I don't like the angle the rod end is on.



Then I'd drop the track bar (or panhard bar) 2" as well.



But, to be honest, I don't I'd worry about 2".



Doing some quick math and using some fake numbers .....



let's assume the track bar is horizontal and 36" long, a 2" raise would amount to . 056" side shift.

 

[Spooled-up]

A track bar is needed in a coil setup regardless of IFS or not.

In an A-arm setup, you wouldn't need a track bar as there is no external axle to speak of. I believe the original Hummers had a setup like this.

 

[Macker]

leveling kit

not to add any fuel to the fire, would you also have to do all of this to a 2wd ??????

 

[ThomasLawrence]

A track bar is needed in a coil setup regardless of IFS or not.

An IFS system doesn't have any lateral movement possible, so there is no need for a track bar. The A arms are mounted to the frame, as is the differential.

let's assume the track bar is horizontal and 36" long, a 2" raise would amount to . 056" side shift.

You added a decimal place there somewhere



Yes, if the track bar were horizontal to begin with, you'd be right. But it isn't. I'm not able to measure it right now, but if we assume it's about 10°, a 2" drop results in about . 41" of shift.



In practical terms, we know a 2" lift displaces the front axle about . 25", so the actual angle of the track bar is less than 10°.



In either case, I agree that a 2" lift doesn't shift the axle enough to make it a concern. In fact, most companies' 3" lift kits for the earlier Rams didn't include any track bar relocation.

 

[JHardwick]

Actually, the IFS I had in mind was the leaf sprung type that that other company used to use, lol.



Seems our math is is close even though I came up with . 411", LOL.



Yeah, besides the numbers not working out, 10* would be 6. 25" of drop from end to end, probably closer to 3 or 4* and longer than 36"

 

[Macker]

level????

a quick question... . you guys are talking alot about doing extra work to your front end after you level it... do any of you think the 2WD needs all of this also, or is it only because you have 4WD????

 

[rbattelle]

Re: level????

Originally posted by Macker

a quick question... . you guys are talking alot about doing extra work to your front end after you level it... do any of you think the 2WD needs all of this also, or is it only because you have 4WD????

I believe it's mostly due to the recirculating ball arrangement and the solid front axle on 4wds. 2wd trucks have a rack-and-pinion arrangement.