Caster shims on factory setup…

Chickeniam

Tremor Member
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Location
NE WI
Current Ride
2023 F250 XLT Tremor
What will happen? I’m hopeing the wandering steering goes away. The truck is great but not that fun to drive. On highway especially in windy conditions, it’s terrible. Correcting constantly and all over the lane. -no lift all stock I’m putting the 2 degree caster shims in today and will get aligned at some point. What are correct settings for alignment? Did camber also adjust during caster shim change?
 

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Here's a photo of my factory ones. I installed the SPC 2º Carli shims. No camber was marked on the SPC shims.

qhIl0R1.jpeg
 
What will happen? I’m hopeing the wandering steering goes away. The truck is great but not that fun to drive. On highway especially in windy conditions, it’s terrible. Correcting constantly and all over the lane. -no lift all stock I’m putting the 2 degree caster shims in today and will get aligned at some point. What are correct settings for alignment? Did camber also adjust during caster shim change?
Just an FYI, Duratracs.

In my case, though they were worse when new, as my tires wore down, it reduced some of the wandering but not 100%. My wandering went away as soon as I changed tires. The original Duratracs are known to cause wander. Reducing air pressure may help as well.
 
Agree it could be the duratracs. The first 2-3000 miles on mine were a PITA but after about 3000 miles the tires started tracking better. Still not a fanboy of the stock duratrac tires but I’m not spending the money on a new set until these are worn….but I don’t plan on rotating them often either so I might be buying tires in about a year. I drive 30k miles a year and got my 24 in January.
 
There was already a lengthy thread that covered al of this. A quick search should bring it up.

It's not the Duratracs. I ran my Duratracs for 67,000 miles and then a set of Coopers for another 20,000 miles before installing the caster shims. As I've written about, I installed 2 degree shims and a dual steering stabilizer with Bilstein stabilizer shocks. That improved the driving significantly. Much better than anytime before. No more constant steering to keep it in the lane. I just got back from a 5,000 mile trip with gear in the truck and a 7,800 lb trailer on the back. Steering was excellent. Now at 96,000 miles.

It is not the tires. It's the caster. The tires may have some minor problem of their own, but the caster angle is the real problem.
 
Agree it could be the duratracs. The first 2-3000 miles on mine were a PITA but after about 3000 miles the tires started tracking better. Still not a fanboy of the stock duratrac tires but I’m not spending the money on a new set until these are worn….but I don’t plan on rotating them often either so I might be buying tires in about a year. I drive 30k miles a year and got my 24 in January.
In my case, the new Duratrac RTs fixed the problem. The three-ply wall and construction are much better than the original. Since I'm the only driver of this vehicle for over a year, I could certainly feel the difference with the new tires. Instantly. No wear in.

Some trucks may need more of an adjustment than others, hence some replace the shim. I did not have that issue myself.
 
What will happen? I’m hopeing the wandering steering goes away. The truck is great but not that fun to drive. On highway especially in windy conditions, it’s terrible. Correcting constantly and all over the lane. -no lift all stock I’m putting the 2 degree caster shims in today and will get aligned at some point. What are correct settings for alignment? Did camber also adjust during caster shim change?
Do you know what the Caster is at currently?
 
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Reading off an alignment machine, caster over 3* is prime for these trucks running stock suspension or tires.
 
Agree it could be the duratracs. The first 2-3000 miles on mine were a PITA but after about 3000 miles the tires started tracking better. Still not a fanboy of the stock duratrac tires but I’m not spending the money on a new set until these are worn….but I don’t plan on rotating them often either so I might be buying tires in about a year. I drive 30k miles a year and got my 24 in January.
Ok makes sense, I’m at 6k. I always liked KO2 BFG for there performance. Likely my next set
 
Just curious if you have an update on your caster shims experiment. Did it improve your steering/wondering? What was your results on your alignment afterwards?
 
It did seem to help. Install was very easy when truck is new. I have not gotten it aligned yet. Tires are likely still the remaining cause to being perfect!
 
I have the BD version. I would like to get them installed, I just don't have the time or inclination to do it myself.

I have a truck that feels like it darts around and has no steering centre driving down the road.

Ford kept the same Super Duty radius arms across all trucks, with our factory Tremor lift the factory caster is reduced. I figure the extra caster will help increase steering "return to centre".

 
I thought I read somewhere that the 24 MY trucks have a different caster setup? I bought some 2* shims but haven’t installed them yet.
 
I thought I read somewhere that the 24 MY trucks have a different caster setup? I bought some 2* shims but haven’t installed them yet.
you need to be careful with the 2* on the '24. there have been reports of them causing the axle to grind. 1* seems to be ok
if you have the dummy passenger hub, you need to replace that as well
 
you need to be careful with the 2* on the '24. there have been reports of them causing the axle to grind. 1* seems to be ok
if you have the dummy passenger hub, you need to replace that as well
This makes about as much sense to me a changing your blinker fluid every 5000 miles. How can caster shims make an axle "grind" and what difference does it make if one hub does not unlock?
 
I’ve seen posts where people question if offsetting the knuckle back 2° was enough to make the axle shaft bind somewhere and it spinning all the time would make it worse.

not sure if anyone has actually experienced that or if it’s just people worrying about it.
 
I’ve seen posts where people question if offsetting the knuckle back 2° was enough to make the axle shaft bind somewhere and it spinning all the time would make it worse.

not sure if anyone has actually experienced that or if it’s just people worrying about it.

when a leading suspension manufacture who sells them in their kits, says not to use them on the '24s and instead to run 1° shims that makes me wonder. And the fact the factory has released a bulletin about the grinding passenger hub, and they are replacing them for free, seems to be a strong argument.
 
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