Caster Shims, Necessary?
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What's your current caster angle?
Yes, if they are installed correctly
If my memory serves me correctly, I think Nolen installs 4* shims on all of his builds with lift springs, and I've only ever seen him use the 2"-2.5" kits on the market. So, you could likely benefit from more than 2* caster shims with a stock housing.....
Not with manual steering.Yes, if they are installed correctly
If my memory serves me correctly, I think Nolen installs 4* shims on all of his builds with lift springs, and I've only ever seen him use the 2"-2.5" kits on the market. So, you could likely benefit from more than 2* caster shims with a stock housing.....
On the front go with 4 degrees, on the back its all about dialing in your diff and pinion flanges to eliminate any vibes.
They are if you want nice steering in the front and no odd u-joint vibrations in the rear. But as has been said, you want to measure both your caster and your driveshaft/u-joint angles, and not just guess.
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Thanks for the responses.
I should have been more clear, I didn’t measure any angles, I have manual steering and I really don’t have any specific driveline vibrations that I can feel. When I posed the question I was only thinking of the front axle.
I asked because it is an industry standard lift, a 40 series with an OEM 2.5 lift. So its a what is everyone else doing?
On my 80 with a 2.5-3 inch lift I automatically added some caster correction.
I should have been more clear, I didn’t measure any angles, I have manual steering and I really don’t have any specific driveline vibrations that I can feel. When I posed the question I was only thinking of the front axle.
I asked because it is an industry standard lift, a 40 series with an OEM 2.5 lift. So its a what is everyone else doing?
On my 80 with a 2.5-3 inch lift I automatically added some caster correction.
When I installed my 3” Alcan lift, I had to shim both the front and the rear, but I don’t remember how many degrees on the front, it’s been at least 15 years. Let me look in my files and old posts and see if I can find it.
How's it drive? Does the steering wheel return after a turn? Negative caster gives a feeling of chasing small corrections or a feeling of a little twitchyness. White knuckle driving, concentrating to stay in its lane. The slight ruts in road effect handling. A small correction becomes exaggerated. A wobbly wheel on a grocery cart has lot of negative caster.
RevISK
SILVER Star
Bob, I put 4* correction shims in the front and it made a huge difference in how my 40 handled.
Approximately 2” lift.
33” tires.
Saginaw Power steering (3.5 turn box).
Bryan @OlYellr has my same setup but manual steering, perhaps he’ll chime in as well?
Approximately 2” lift.
33” tires.
Saginaw Power steering (3.5 turn box).
Bryan @OlYellr has my same setup but manual steering, perhaps he’ll chime in as well?
RevISK
SILVER Star
But yes, measure your caster angle first. The reason so many go with 4* is that they are around 1-2* negative after a lift.
OlYellr
SILVER Star
The caster shims was the single best upgrade/fix I did. It made Yellr feel so much safer. Like mentioned mentioned… shopping cart but sans wobble. It was the difference for me feeling safe taking a curve in the road at 45 then vs 60/65 now on the highway (speed limit is 65). I only have from shims.
I never really think if how I have to steer it back after a turn (no power steering)
And Ian, @RevISK is right with the calculus. I have 4 degree on mine. IMO, enough have that lift height, stock diff/propeller shaft setup that the 4 degree shims are proven to be a reliable addition. If you have something different, use a larger shim, or just want to learn vs take someone else word for buying parts, measure it.
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Of course my 43 wonders! I chase it side to side constantly! I was thinking it was my 40 year old TRE’s or my center arm causing the wonder? As I reviewed my wondering issues it made me think of the caster shims and how they could make a difference. Sounds like it will? It’s funny because I didn’t think twice about castor correction for my 80 after a lift.
@Ol Yeller and Ian did you guys shim the rear?
Thanks everyone for chiming in. I’ll get back to this in many days from now after I do the Fing work.
This reminds me of a quote from JRR Tolkien “all who wonder are not shimmed”
Peace out!
@Ol Yeller and Ian did you guys shim the rear?
Thanks everyone for chiming in. I’ll get back to this in many days from now after I do the Fing work.
This reminds me of a quote from JRR Tolkien “all who wonder are not shimmed”
Peace out!
RevISK
SILVER Star
My trucks didn’t need them in the rear.
Measuring the angle can be a little confusing, especially in the front, but it’s worth doing if nothing more than getting a data point.
Call me if you have questions.
RevISK
SILVER Star
Oh, probably wouldn’t hurt to put new TREs in there as well.
How are your bushings?
I don't have them on mine.
2½" suspension
Saginaw Power steering
31x10½ tires.
It might benefit from them, but what i notice the most is when a road is pounded in and my track width doesn't match the ruts in the pavement. Not sure much can be done about that.
2½" suspension
Saginaw Power steering
31x10½ tires.
It might benefit from them, but what i notice the most is when a road is pounded in and my track width doesn't match the ruts in the pavement. Not sure much can be done about that.
Shims should help it track better. Especially with a worn road.
Why I don't think it'd do much is that affects every vehicle I've ever driven
A number of years ago I helped a friend install 4" pro comp springs on his 40. A couple of weeks later he called me and said the 40's was handling bad, so I went over his house and measured his caster angle and I told him to order 4* shims. About a week later he received the shims and he called me to asked how to install the them. About an hour later he called me back and the 1st words I heard was "That's amazing". He couldn't believe what a few degrees could do for handling.
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