True, but if it's not tracking straight, the tracks will show it. For example, if the tracks go left front, left rear, right front, right rear, that would indicate a dog leg situation
Help! Dog Tracking!!
- Thread starter MrMopar
- Start date
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True, but if it's not tracking straight, the tracks will show it. For example, if the tracks go left front, left rear, right front, right rear, that would indicate a dog leg situation
It is just so much easier to follow it and check it on both sides or do the string line.
It will not necessarily show four tracks. If the front does not completely eclipse the rear, there will only be two tracks. Some of yall are overthinkin this. It's not that difficult a problem.
TheTecher
Evan the jeeper.
You could have toe in on one tire and toe out on the other.
Quick check as mentioned before is to wet your driveway down and drive thru the water.
You can tell a lot of what is going on.
I remember the nova's breaking the center pins.
My buddy was driving his home from the paint shop, nice shiny orange paint.
Center pin broke, and it threw him over the hill tearing the passenger side of the car all up.
You can tell a lot of what is going on.
I remember the nova's breaking the center pins.
My buddy was driving his home from the paint shop, nice shiny orange paint.
Center pin broke, and it threw him over the hill tearing the passenger side of the car all up.
Unless they've worn dead evenly over time (not likely), bad spring eye bushings on a live rear axle sprung with semielliptics will cause some degree of dogtracking and the odds are how much will constantly change with every input of load, coast, and brake, and every bump in the road. If that's the case, no amount of getting the static rear axle alignment perfect is going to mean much. If the spring eye bushings are not worn and are perfectly centered in their spring eyes (good luck with that unless the bushings are relatively new), unlike a semi elliptical sprung rear axle on a Ford or Chevrolet that usually require cutting and/or welding to properly fix rear axle thrust angle, 1/2 degree on an A body rear axle should be easily adjusted out. This is because the front leaf spring hanger bolts in allowing you get the rear axle dead nuts perpendicular the center line of the car, usually with just a shim or two.
I used to poo-pa four wheel alignments on my Camaros and Mustangs because if you had a problem beyond worn bushings, there wasn't much you could do about it short of structural modification (welding, drilling, cutting, etc.), but it really makes sense to have a good four wheel laser alignment (thanks to all the independent rear suspensions and front drive cars out there these days, a lot of times you aren't given a choice) done on any of the live axle rear drive Mopars. If you do step up and have the a four wheel alignment done and the thrust angle is off, I'd be making sure the shop will shim your axle to get it correct, or retest for free if you have to do it.
While skewing the rear axle may be the hot setup at times on a circle track, keeping the rear axle pointing straight ahead is an imperative for a predictable, easily driven car otherwise.
I used to poo-pa four wheel alignments on my Camaros and Mustangs because if you had a problem beyond worn bushings, there wasn't much you could do about it short of structural modification (welding, drilling, cutting, etc.), but it really makes sense to have a good four wheel laser alignment (thanks to all the independent rear suspensions and front drive cars out there these days, a lot of times you aren't given a choice) done on any of the live axle rear drive Mopars. If you do step up and have the a four wheel alignment done and the thrust angle is off, I'd be making sure the shop will shim your axle to get it correct, or retest for free if you have to do it.
While skewing the rear axle may be the hot setup at times on a circle track, keeping the rear axle pointing straight ahead is an imperative for a predictable, easily driven car otherwise.
Very well put! Go up a few threads and comment on the measurements that were taken during my alignment. It shows the thrust angle and the rear toe. I am curious to read your findings. Now remember, when I tried to adjust the rear toe, it made it worse.Thanks guys.
Your thrust angle is not that bad, but if you want to improve it, put the shims on the driver side. It will not change the toe, but will improve the trackage.
The thrust angle is a non adjustable angle on a Mopar. It is a comparison of the vehicle centerline to the rear axle centerline as viewed from the top of the car. The only way to adjust it would be to move the spring perches. You might can make some very small adjustments by loosening the rear axle U blots and trying to move the rear axle, but it will probably not be much at all. The only adjustment on the rear regarding shims is the pinion angle, not the thrust angle. The only other way would be to try to compensate for the incorrect thrust angle with the front end alignment....but again, since the thrust angle is a measuerment regarding the rear axle relationship, you're sorta putting a bandaid on the problem. Best bet is to get it on the rack and CONFIRM what the problem really is and go from there. Because all this batting it around online is guesswork at best.
I will add this.....you MIGHT could get a little adjustment by making some shims to put between the front spring hanger and the hanger mount, but this is really not an accepted method. IF the thrust angle is out and all of the bushings are in good ahape and intact, I would be lookinf for possible previous crach damage regarding the frame rails. BUt of course, as I said, ALL of this is guesswork until it sees an alignment rack.
Here is a shim kit: http://www.jegs.com/i/Hotchkis/515/3003/10002/-1?parentProductId=1348322
I will add this.....you MIGHT could get a little adjustment by making some shims to put between the front spring hanger and the hanger mount, but this is really not an accepted method. IF the thrust angle is out and all of the bushings are in good ahape and intact, I would be lookinf for possible previous crach damage regarding the frame rails. BUt of course, as I said, ALL of this is guesswork until it sees an alignment rack.
Here is a shim kit: http://www.jegs.com/i/Hotchkis/515/3003/10002/-1?parentProductId=1348322
Thank You, I am aware of the shim pack from Hotchkiss. It is the only way to get the thrust angle back to zero, as far as I can see. There must have been a problem with this or Hotchkiss would not have made a shim kit to correct it. It may be more common than you think. 6pk2goDemon is right, I am installing the shim and going to the alignment rack to have it checked.
No, it's not the only way. A lot of the time, if the thrust angle is out enough to actually see it is too far out of spec for shims to correct. At least not without stacking them to thickly. In that instance, it's time for the frame machine. That's why I recommended the alignment rack first, because you never know, it may only be the front being out of alignment causing that illusion. I've seen it a lot. I did my first alignment in 1974 and it's how I made my living, so I know just a little about it. Good luck with it. I am sure you'll get it sorted out.
I am not disputing your claim, I trust you know what you are talking about. I am at .41 degrees positive thrust angle which isn't too much, just a little off zero. I went for another cruise tonight and had my friend drive down the centre of the highway and I could see the passenger front tire from my vantage point but not as much as the drivers side when following behind in the correct lane. It is true that the front wheels are set apart wider and that just proved it, and I measured also. So I am looking at a small correction and an illusion when being followed. Not too much to worry about, just enough to bug me!
Is that measured in degrees or inches? If it's degrees, there's no need to worry. lol ...and I wasn't trying to brag....I was letting you know I was not simply randomly throwing out info. Wasn't arguing in the least, quite the contrary. Simply agreeing with all said and adding to. Good luck.
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