bump steer
- Thread starter sponhower
- Start date
mattw
Active member
Re: bump steer
Jeff, I know you posted before what alignment tools you use but I can't find that info. So my question is, what are you using and would you buy the same tool again or has something better come along that you would choose over what you have?
I did a quick search on ebay for alignment gauge and it seems that there are a lot more choices now than there were a few years ago..
After 6 years of not being on the road my truck is finally ready for an alignment and some road time and I'd much prefer just to do it myself than take it to a shop...
Jeff, I know you posted before what alignment tools you use but I can't find that info. So my question is, what are you using and would you buy the same tool again or has something better come along that you would choose over what you have?
I did a quick search on ebay for alignment gauge and it seems that there are a lot more choices now than there were a few years ago..
After 6 years of not being on the road my truck is finally ready for an alignment and some road time and I'd much prefer just to do it myself than take it to a shop...
Andrew S
New member
Re: bump steer
^ THIS!
I remember reading a couple of threads where guys were just dropping in rack-and-pinions out of explorers or anything that would fit and there was no mention of measurements or a bump steer gauge or anything. I can only imagine how horribly the vehicles handled after doing this.
As mentioned above I would wager your are experiencing tram-lining due to wider and/or softer compound tires.
When I chose the wrong front coils for my 2wd s10 it lowered it twice what I was hoping for, I experienced bump steer at high speeds and only over very severe bumps but even then it was minimal. There is aftermarket "bump steer kits" which lower the tie rod at the spindle to align the pivot points.
A bump steer gauge can be quite easily fabricated. All you really need is a dial indicator or ideally 2 of them and a little jig to hold them solidly in place. Then you cycle the suspension, and measure the amount of bump steer.
edit*
and ^this!
As you say they teach them how to do it, not why* they are doing it. I've had some bad experiences with guys doing alignments and never again will I let one of them touch my truck. I don't hate tech's, it's just why pay someone to do something as simple as an alignment when you can do it yourself in less then an hour with a simple gauge and some string-line. Anyway, I digress.
^ THIS!
I remember reading a couple of threads where guys were just dropping in rack-and-pinions out of explorers or anything that would fit and there was no mention of measurements or a bump steer gauge or anything. I can only imagine how horribly the vehicles handled after doing this.
As mentioned above I would wager your are experiencing tram-lining due to wider and/or softer compound tires.
When I chose the wrong front coils for my 2wd s10 it lowered it twice what I was hoping for, I experienced bump steer at high speeds and only over very severe bumps but even then it was minimal. There is aftermarket "bump steer kits" which lower the tie rod at the spindle to align the pivot points.
A bump steer gauge can be quite easily fabricated. All you really need is a dial indicator or ideally 2 of them and a little jig to hold them solidly in place. Then you cycle the suspension, and measure the amount of bump steer.
edit*
and ^this!
As you say they teach them how to do it, not why* they are doing it. I've had some bad experiences with guys doing alignments and never again will I let one of them touch my truck. I don't hate tech's, it's just why pay someone to do something as simple as an alignment when you can do it yourself in less then an hour with a simple gauge and some string-line. Anyway, I digress.
Last edited:
Flyin Ryan
hated cuz he drives fords
JSM
Active member
Re: bump steer
swivel plates just help you turn easier, i've never had issue starting the truck and turning it with power steering. Well they are suppose to keep some bind out of system also, but it hasn't been an issue.
The gauge I posted, notice the end has angles cut on it, guess what those angles happen to be 20 degrees. Hmmmm, wonder why they would do that. I add a ruler to it to help be a bit more accurate but it works. No need to go buy all the fancy stuff.
As far as adaptor I didn't find one off the shelf that worked on our trucks, didn't look very hard either being I have a lathe. I made my own that slides over the axle once you remove the center cap.
swivel plates just help you turn easier, i've never had issue starting the truck and turning it with power steering. Well they are suppose to keep some bind out of system also, but it hasn't been an issue.
The gauge I posted, notice the end has angles cut on it, guess what those angles happen to be 20 degrees. Hmmmm, wonder why they would do that. I add a ruler to it to help be a bit more accurate but it works. No need to go buy all the fancy stuff.
As far as adaptor I didn't find one off the shelf that worked on our trucks, didn't look very hard either being I have a lathe. I made my own that slides over the axle once you remove the center cap.
JSM
Active member
Re: bump steer
I put a ruler and look at side of the car, a few degrees off when turning doesn't change caster measurement very much at all its not that critical.
I suspect you got friends with a lathe that might help you out.
I put a ruler and look at side of the car, a few degrees off when turning doesn't change caster measurement very much at all its not that critical.
I suspect you got friends with a lathe that might help you out.
alwayscode390
pppssssshhhhhtttttttttttt
Re: bump steer
How wide are your tires... wide tires definately follow the grooves in the road ---
How wide are your tires... wide tires definately follow the grooves in the road ---
mattw
Active member
Re: bump steer
So I bought a caster/camber gauge..
$103.75 total shipped to my door.
Its possible to order these with adapters that thread right on the axle spindle bolt but I opted for the magnetic mount. My plan is to make a fixture for each wheel that will hold this gauge and allow me to accurately measure toe in and toe out..
This is what the mount looks like.. So it would also be possible to remove the guage from the magnetic base and mount it right on the fixture that I build:
Finally, here are the instructions that came with it:
Sounds easy enough..
I've got two vehicles to align so this tool will pay for itself right away...
So I bought a caster/camber gauge..
$103.75 total shipped to my door.
Its possible to order these with adapters that thread right on the axle spindle bolt but I opted for the magnetic mount. My plan is to make a fixture for each wheel that will hold this gauge and allow me to accurately measure toe in and toe out..
This is what the mount looks like.. So it would also be possible to remove the guage from the magnetic base and mount it right on the fixture that I build:
Finally, here are the instructions that came with it:
Sounds easy enough..
I've got two vehicles to align so this tool will pay for itself right away...
alwayscode390
pppssssshhhhhtttttttttttt
Re: bump steer
Last time I had an alignment I told the guy to get me as low as he could in the front with the torsion bars ... but I wanted a good alignment that wouldnt wear my tires. This is what he came up with:
If you look at the pic the top of my tires are pointed in quite a bit. It handled GREAT ... but with these crappy Falken tires, I was almost seeing cord on the inside of my tire after 9k miles!!!
Is there a camber/caster kit they sell for our trucks ... like they do when you lower your vehicle with an adjustable setup (coilovers)?
I just put new tires on the other day and would hate to eat them up again like I did the last set.
THANKS
---
Last time I had an alignment I told the guy to get me as low as he could in the front with the torsion bars ... but I wanted a good alignment that wouldnt wear my tires. This is what he came up with:
If you look at the pic the top of my tires are pointed in quite a bit. It handled GREAT ... but with these crappy Falken tires, I was almost seeing cord on the inside of my tire after 9k miles!!!
Is there a camber/caster kit they sell for our trucks ... like they do when you lower your vehicle with an adjustable setup (coilovers)?
I just put new tires on the other day and would hate to eat them up again like I did the last set.
THANKS
---
mattw
Active member
Re: bump steer
So actually doing the alignment is challenging the first time around. I spent about 2 hours on the first wheel. I'm not sure if I was approaching it the best way or not. I would set the camber and then check the caster. If the caster wasn't where I wanted it I would straighten the wheel back out, make adjustments, get the camber where it needed to be then check the caster again..
After about an hour I started to get a good idea of how my adjustments would change the caster..
The second wheel only took me about 20 min.. I would imagine that after you do it a few times it would probably only take about 10 min per wheel...??
I still need to set the toe in/out and then it should be good.. I ran out of time but I can't imagine this part will take all that long..
I have both wheels currently set to:
Camber = -1/4
Caster = +6
I'll probably toe it in just a tiny bit. Not more than an 1/8"..
So actually doing the alignment is challenging the first time around. I spent about 2 hours on the first wheel. I'm not sure if I was approaching it the best way or not. I would set the camber and then check the caster. If the caster wasn't where I wanted it I would straighten the wheel back out, make adjustments, get the camber where it needed to be then check the caster again..
After about an hour I started to get a good idea of how my adjustments would change the caster..
The second wheel only took me about 20 min.. I would imagine that after you do it a few times it would probably only take about 10 min per wheel...??
I still need to set the toe in/out and then it should be good.. I ran out of time but I can't imagine this part will take all that long..
I have both wheels currently set to:
Camber = -1/4
Caster = +6
I'll probably toe it in just a tiny bit. Not more than an 1/8"..
mattw
Active member
Re: bump steer
I built the fixtures. The are 1" square aluminum stock and the plate up front is just 1/8" mild steel. I compared the fixtures to a known good straight edge but I really don't have any other way to make sure they are true.. I drilled and tapped the aluminum and there are actually 1/4-20 bolts that contact the surface of the rim. I did measure these with my micrometer and they were right on so I didn't make any adjustment to them...
I guess the real test will be how it performs on the road and how well the tires wear..
I built the fixtures. The are 1" square aluminum stock and the plate up front is just 1/8" mild steel. I compared the fixtures to a known good straight edge but I really don't have any other way to make sure they are true.. I drilled and tapped the aluminum and there are actually 1/4-20 bolts that contact the surface of the rim. I did measure these with my micrometer and they were right on so I didn't make any adjustment to them...
I guess the real test will be how it performs on the road and how well the tires wear..
mattw
Active member
Re: bump steer
I highly doubt it..
So I drove it today.. Not very far.. Maybe a mile total.. I learned a few things..
1) Tuning is difficult. You really need two people when your tune isn't even close!!
2) The alignment seems dead on. No bump steer. Didn't want to follow groves and tracked straight..
3) The rack and pinion works perfectly.. No bump steer, no slop in the steering, no binding. It just feels like a newer and tighter vehicle that came from the factory with R&P... Much nicer!
I highly doubt it..
So I drove it today.. Not very far.. Maybe a mile total.. I learned a few things..
1) Tuning is difficult. You really need two people when your tune isn't even close!!
2) The alignment seems dead on. No bump steer. Didn't want to follow groves and tracked straight..
3) The rack and pinion works perfectly..
No bump steer, no slop in the steering, no binding. It just feels like a newer and tighter vehicle that came from the factory with R&P... Much nicer!
mattw
Active member
Re: bump steer
I worked on the tune some more.. I have AFR hanging out on the safe(rich) side now so I felt comfortable driving further.. I drove it from the shop to my house(about 2.5 miles). I hit about 50 MPH and lots of rough roads.. Still very happy with how everything is working. I think my next focus needs to be heat shields and exhaust wrap. Stuff gets really hot on the turbo side of the engine...
I worked on the tune some more.. I have AFR hanging out on the safe(rich) side now so I felt comfortable driving further.. I drove it from the shop to my house(about 2.5 miles). I hit about 50 MPH and lots of rough roads.. Still very happy with how everything is working. I think my next focus needs to be heat shields and exhaust wrap. Stuff gets really hot on the turbo side of the engine...
JSM
Active member
Re: bump steer
Never seen a dead level floor either, or a dead perfect "alignment tech" guy.
Is this bubble gauge perfect, and setup perfect NOPE.
Does it work and work well, YES.
Never seen a dead level floor either, or a dead perfect "alignment tech" guy.
Is this bubble gauge perfect, and setup perfect NOPE.
Does it work and work well, YES.
mattw
Active member
Re: bump steer
I just used the alignment tool and fixtures to align our 99 Jimmy. I tried to find the factory alignment specs online and didn't have any luck.. So, I just used the same settings I used for my clone..
Caster +6
Camber -1/4
Toe in 1/8"
Over the past couple of years I've noticed the steering in this vehicle get sloppier and sloppier.. Everything seemed tight so I just assumed the steering box was getting loose.. I'm amazed at how much better it is now that I've aligned it with these specs.. Its no longer a chore to drive it down the highway.. This vehicle gets used considerable more than my clone so I should be able to report back on tire wear relatively soon..
I just used the alignment tool and fixtures to align our 99 Jimmy. I tried to find the factory alignment specs online and didn't have any luck.. So, I just used the same settings I used for my clone..
Caster +6
Camber -1/4
Toe in 1/8"
Over the past couple of years I've noticed the steering in this vehicle get sloppier and sloppier.. Everything seemed tight so I just assumed the steering box was getting loose.. I'm amazed at how much better it is now that I've aligned it with these specs.. Its no longer a chore to drive it down the highway.. This vehicle gets used considerable more than my clone so I should be able to report back on tire wear relatively soon..
ndburli
New member
Re: bump steer
So you set the front tires to these specs...what about the rear axle? Did you do a thrust angle alignment to see if it is tracking correctly? Reason I ask I am getting an alignment done Thursday but didn't know if shops have the specs for these trucks. Anyone know if the specs are common?
So you set the front tires to these specs...what about the rear axle? Did you do a thrust angle alignment to see if it is tracking correctly? Reason I ask I am getting an alignment done Thursday but didn't know if shops have the specs for these trucks. Anyone know if the specs are common?