alignment results

[75chev4x4]

Hey guys been working through a wandering problem with my 75 k20 truck and wanted to see what you guys thought about my aligmnet specs. Since I have had this truck it has always wandered around going down the road. I have replaced the ball joints, tre, dre, leaf springs 2" lift all the way around, borgeson steering shaft, new steering box, shocks, steering stabalizer, drop pitman arm so the drag link is flat, had the tires balanced, and had it aligned. Long story short the thing is still all over the road and not fun to drive. I'm trying to figure out what else could be wrong that I'm overlooking otherwise I'm going to get rid of it cause I'm into this thing 8k and its still drives poor at best. Anyway wanted to put up my alignment specs from last week when I had it in to be aligned. No other work has been done to it except for the borgeson shaft I just put on.

Left front
Camber 0.3 degrees
Caster 3.7 degrees
Toe 0.19 degrees

Right front
Camber 0.5 degrees
Caster 3.9 degrees
Toe 0.20 degrees

Total toe 0.39 degrees
Steer ahead -0.01 degrees

Does this seem about right for this truck with a 2" lift? Tires are 265/75/16, thanks for looking!

[76stepsidechevy]

Are there shims on the front spring to correct the pinion angle?

[75chev4x4]

No shims on the front springs.

[75chev4x4]

Couple shots if this helps. I'm out here looking at the center link and is it possible it is on upside down? The threads are facing down on both ends? That or I'm just getting crazy and thinking everything is wrong haha. Thanks.

[425HP409]

I do alot of alighments in my shop on older vehicles and have found the following information to be helpful. The toe in specs for the older vehicles were in inches, but the new alignment machines read in degrees. The Caster and Camber look OK on your specs, but you have too much toe in. You want 1/16" to 1/8" total toe, this correlates to .08-.16 degrees. With .39 degrees, total toe, in you have over 1/4" toe in, which will make the truck wander big time.
ps. I have been doing alignments since 1963
Charles

[75chev4x4]

Ok very good to know. Thank you 425hp409. I'm a younger guy and love working on these older trucks and its really satisfying to get advice from guys who have worked on the for a long time. I have been taking it to firestone for alignments but I might go find a small shop that is better at these trucks and see if they can get it where it should be.

[86c20]

one thing to think of is the tires them selfs (belts bad will do it) and bearings also. if you have bigger tires on already weak baerings??? what about the springs and cupps in the axle its self? that one i dont know but would think that 425hp409 may??? do you get a shimmy when breaking only some times? that is what my k30 is dooing and was told springs and cups.

[75chev4x4]

Doesn't really shimmy might pull very slight to one side but not much. Tires are in good shape and not too big Imho. Just for kicks I was this ki g about putting my dads wheels and tires off his f250 on my truck and take it for a drive see if there is a difference. New bfg at 285/75/16 so should be close to mine.

[425HP409]

The thing about aligning the older vehicles, you have to set it up according to the factory specs that were in effect at the time the vehicle was built. Your alignment tech will have to ignore the "preferred settings" that the alignment computer will have and just set it up according to the earlier settings.

[75chev4x4]

Originally Posted by 425HP409

The thing about aligning the older vehicles, you have to set it up according to the factory specs that were in effect at the time the vehicle was built. Your alignment tech will have to ignore the "preferred settings" that the alignment computer will have and just set it up according to the earlier settings.

Ok. Just looked in my Chilton and they say 0 toe in on the 4wd models. Any advantage to that vs a little 1/16 toe in? Thank you sir.

[Desert1957]

Originally Posted by 75chev4x4

Ok. Just looked in my Chilton and they say 0 toe in on the 4wd models. Any advantage to that vs a little 1/16 toe in? Thank you sir.

Yes on the Toe setting, Think of it this way.
GM and most manufactures are trying to achieve a 0 toe setting while going down the road , so a 1/8 setting works out to about 0 with the normal resistance on the front tires going down the road.

Any more than 1/8 toed in and one tire will always be toed in while the other is straight, causing constant correction of the steering wheel or road wander.

There are many things in the front end that add up to too much play overall , pitman arm , idler arm, steering box adjustment, recheck all parts fo ANY play before condemning alignment specs.

Desert

[75chev4x4]

Originally Posted by Desert1957

Yes on the Toe setting, Think of it this way.
GM and most manufactures are trying to achieve a 0 toe setting while going down the road , so a 1/8 setting works out to about 0 with the normal resistance on the front tires going down the road.

Any more than 1/8 toed in and one tire will always be toed in while the other is straight, causing constant correction of the steering wheel or road wander.

There are many things in the front end that add up to too much play overall , pitman arm , idler arm, steering box adjustment, recheck all parts fo ANY play before condemning alignment specs.

Desert

I think I'm in good shape on the parts of the front end. Everything is new and the shop said it was really tight. Everytime i have done a dry park everything seems to move together, not super inpressed with my napa reman box but its better than the old one. So if I wanted an overall toe in of. 08 would they set both sides to .04 or does the crown of the road have some effect on this with one side getting more than the other? Thanks.

[Desert1957]

Yes but converting 1/8 to digital is (.125)
they measure toe , overall
Desert

[75chev4x4]

Originally Posted by Desert1957

Yes but converting 1/8 to digital is (.125)
they measure toe , overall
Desert

Ok

[425HP409]

I agree with Desert1957, the total toe when going down the road is ideally 0. The alignment tech has to make sure to push out on the front of the tires before taking a toe reading to eliminate any slack in the linkage as this is what happens when you are driving. When you set the total toe in at 1/16 to 1/8 on the rack, the tires will have a net toe of 0 degrees when driving, thus no wandering or excessive abnormal tire wear.

[75chev4x4]

Ok thanks. I hope this is what the problem is with this truck cause I really like it otherwise. I have taken it to the same firestone three times for an alignment so I don't know if I should take the specs in there and tell them that it drives like crape the way they have it set or just go find a shop that only does alignments. The only reason I would take it back to them is because i bought the lifetime alignment.

[1LowToy]

I'm seeing the inside edge of your tire tread which looks like new. Willing to wager the outside edge has some wear. That tells me it's towed in. The steering geometry is more complicated than just throwing the parts on an making the steering wheel straight.

Trying to explain this may be difficult so bare with me. Just having your tow in set to 0 tow in is a good start yes. But if you have on tie rod in in more than the other on th drag link you may be just starting your alignment difficulties. Your spindles are designed to turn your wheel with just so much camber and castor at each degree of the turning motion. So if that is off just the slightest amount the your turning each wheel in the incorrect amount. Many of the drag links of the day were set up incorrectly. Many of the 4x truck of the day the right front tire would wear like mad on the outside edge. The right tire on left turns was turning left further than the left front causing it to scrub horibly. So the only way to correct that was to extend the right tie rod out and the left one in. This was done to correct the steering axcess points between the left and right sides. Then to correct the steering wheel the link between the steering box and the spindle was adjusted to correct the steering wheel alignment. Later models the drag link from the steering box was not adjustible and was designed wrong and would never work well. Chevy's were better than most manufactures but it did happen.

When turning left the right front tire needs to turn a a larger circle so it won't scrub, vs versa on right turns. If this is off just driving down the road or in my case through winding roads can be very spooky.

I had a brand new 89 camaro that this was way off on and it handled horrible. Got the steering straighten out and the only way to correct the steering wheel was to cut another slot on the splins of the steering wheel. Yes on a brand new car. After that it was like a camaro go-cart.

You may be looking for a very savey allingment person to get this corrected.

PS simple check before you go nuts on allignment are your spring and shackle bushings in good shape?

Oh after a second look your drag link is not adjustible on both ends. Your steering access can be checked but is not adjustible.

[75chev4x4]

Yea bushings are all new or in good shape as far as I can tell.

[75chev4x4]

Hopefully its just too much toe in. I cant afford any more parts for this thing its already cost me a small fortune.

[v30crewcab]

Originally Posted by 1LowToy

I'm seeing the inside edge of your tire tread which looks like new. Willing to wager the outside edge has some wear. That tells me it's towed in. The steering geometry is more complicated than just throwing the parts on an making the steering wheel straight.

Trying to explain this may be difficult so bare with me. Just having your tow in set to 0 tow in is a good start yes. But if you have on tie rod in in more than the other on th drag link you may be just starting your alignment difficulties. Your spindles are designed to turn your wheel with just so much camber and castor at each degree of the turning motion. So if that is off just the slightest amount the your turning each wheel in the incorrect amount. Many of the drag links of the day were set up incorrectly. Many of the 4x truck of the day the right front tire would wear like mad on the outside edge. The right tire on left turns was turning left further than the left front causing it to scrub horibly. So the only way to correct that was to extend the right tie rod out and the left one in. This was done to correct the steering axcess points between the left and right sides. Then to correct the steering wheel the link between the steering box and the spindle was adjusted to correct the steering wheel alignment. Later models the drag link from the steering box was not adjustible and was designed wrong and would never work well. Chevy's were better than most manufactures but it did happen.

When turning left the right front tire needs to turn a a larger circle so it won't scrub, vs versa on right turns. If this is off just driving down the road or in my case through winding roads can be very spooky.

I had a brand new 89 camaro that this was way off on and it handled horrible. Got the steering straighten out and the only way to correct the steering wheel was to cut another slot on the splins of the steering wheel. Yes on a brand new car. After that it was like a camaro go-cart.

You may be looking for a very savey allingment person to get this corrected.

PS simple check before you go nuts on allignment are your spring and shackle bushings in good shape?

Oh after a second look your drag link is not adjustible on both ends. Your steering access can be checked but is not adjustible.

This only makes sense on IFS suspensions. the solid axle only has one adjuster, the wheels will automatically divide the toe in order to go straight, adjusting the drag link is only going to center the steering wheel, and the steering box, but won't have any affect on the toe.
I've dialed in my solid axle in the driveway for years. my truck with 4" lift and 35's can be driven at 80 plus all day with one finger. wish I still had an alignment rack to use, but the driveway works just as well on a solid axle.

[75chev4x4]

Originally Posted by v30crewcab

This only makes sense on IFS suspensions. the solid axle only has one adjuster, the wheels will automatically divide the toe in order to go straight, adjusting the drag link is only going to center the steering wheel, and the steering box, but won't have any affect on the toe.
I've dialed in my solid axle in the driveway for years. my truck with 4" lift and 35's can be driven at 80 plus all day with one finger. wish I still had an alignment rack to use, but the driveway works just as well on a solid axle.

Wow that's great! What's your driveway method? I might give it a shot. Thanks

[v30crewcab]

you use a tape measure to measure the front and rear of the tires, at a same tread point, to determine toe. its better to go to the edge of the rim but harder.
4wheel & offroad did a article on it several years back, but I can't seem to locate it. then I adjust the drag link until the steering wheel is straight when you drive it.
also helps to have a tight steering box.
heres a writeup on adjusting it. ONLY do this if you're comfortable messing with it.
http://www.pirate4x4.com/forum/showp...6&postcount=11
most people think theres magic in a steering box, but they're not that hard to work on if you have some patience. heres the full article on rebuilding it.
http://www.pirate4x4.com/forum/showthread.php?t=570869

[Keith Seymore]

In addition to what everyone else is suggesting I'd crank the caster way up.

We used to fix customer complaint vehicles in the Engineering garage that the dealers couldn't fix. We'd put as much as 10 degrees caster in those trucks.

K

[75chev4x4]

I can mess with the toe but I don't know how to change the caster on this truck.

[75chev4x4]

Wow Keith I'm jealous that you got to build these trucks back in the day. That would have been a dream job for me to work in the gm plant. At least back in the day when we were making them here.