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Old 02-03-2019, 12:51 AM   #1
chris989
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How much caster,

Hello, all,

Way back i had a crewcab and after a proper alignmnet it drove horrible. I took it to an old school shop and the man said "those chevys need more caster to run straight". He was right.

Fast forward, I am fine tuning my V2500 burb and it has always darted back and forth a little. When i did my 2 inch springs, I added 2 degrees. I had it checked and it is within spec.

I brought the toe in a little and that helped,,, and I am thinking of adding 2 more degrees to the caster. This will put it right at the max maybe a touch over.

Does anyone know what degree they are running?

Also,, it is a 3/8 center bolt???? I don't have the truck at hand to measure and I was going to order new shims.

Thank you,
Chris
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Old 02-03-2019, 07:11 AM   #2
cadillac_al
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Re: How much caster,

I'm not sure how each degree of caster affects the driveshaft angle but I would be slightly worried. I don't know why my trucks seem to track straight with the stock settings but that's all I've known all my life. My K10 with stock height and K20 with 2" lift seem to roll nice and straight down the highway at 70-80 mph. Let us know how yours turns out with more castor.
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Old 02-03-2019, 01:47 PM   #3
chris989
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Re: How much caster,

cadillac,

The truck rides ok now. Just feels to me like it wants to "roll over to the other side" more often than not.

I have a PSC box with a 180 T-bar (easy to turn). not sure if this is helping.

With my Jeep CJs, I run them ~5 degrees and with the short wheel base it runs straight.

I will throw in a set of 4 degrees and report back. I need to find my alignment print out from before. I think I am already ~7degrees
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Old 02-03-2019, 02:14 PM   #4
kwmech
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Re: How much caster,

If you are at 7 and still have a problem, I would look elsewhere. Factory is about 3-4 and I can relate b'cuz I'm dealing with the same on my '91. My last suburban was a 1990 and I did an axle swap to a D60 and aftermarket springs. made all the difference with a heavier front and lift kit. I think the 1990 ended up somewhere around 5-6 and drove sweet. Get any, what they call "death wobble" ?
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Old 02-03-2019, 06:23 PM   #5
obijuan
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Re: How much caster,

I run 6 degrees from the spring pad being the zero. 91 d60.
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Old 02-03-2019, 09:00 PM   #6
Sabaka454
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Re: How much caster,

Why do you think adding caster will help with your problem? It's already excessive and will lead to instability, shaking and death wobble by continuing to increase caster. By "roll over to the other side" Are you saying it pulls to one side?
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Old 02-03-2019, 11:23 PM   #7
chris989
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Re: How much caster,

I have no wobble, Wobble comes from zero or negative caster. I know my crew cab long bed just would not track straight at factory specs. I will get the last alignment sheet before I add.

I think anything under 10 should be ok for the street. I might even pull the steering box, drain it and check the preload
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Old 04-23-2019, 10:35 AM   #8
chris989
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Update,,, solved

Factory specs for my 89 v2500 is 7.5-8.5 caster. I am running 8.4/8.9.

My problem was with my steering box. When i had it out last time, I set the preload to the tight end of spec, (i think something like 9-12 inch pounds).
I didn't want my steering to wander.

Well, I loosened the preload nut by 1/4 turn and magic, no more memory. drives as it should.

I did run the 4 Degree wedges, (10 degree total caster) drove straight, no wobble but it was definitely too much, I could feel it when turning. there was a lot of resistance trying to make the truck go straight.
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Old 04-23-2019, 07:46 PM   #9
akart
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Re: How much caster,

Did a lift and the steering was light,felt like I was herding chickens. Alignment done and caster was maybe 2 degrees low. Increasing caster or camber can give more resistance but at the cost if tire wear. Solution: Speedway makes a power steering fluid restrictor. goes on the PS pump high pressure line, reduces flow maybe from 3 to 2 GPM. Gives more steering resistance. IMHO I think this is much better than changing installing castor wedges and it's better on the tires and the fittings are about 30 bucks. 2 parts needed the restrictor and s fitting to adapt it and it, installs in a few min. Found this on a thread here a couple of months ago. I could look up the part # if you like.
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Old 11-25-2021, 12:08 AM   #10
chris989
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Solved

Hello all,

Finally after years of constantly fighting the constant steering required to stay straight on the highway I puller the PSC box,

I bought a new Lares 11263. I used Lares on some other builds and always perfect.

I have put a ew hundred miles on the new box (210 T-bar) and the truck drives like a new truck. I can not put into words how much better it is. I had the PSC box out and bench adjust several time and then fiddled with even more after install and never any luck.

Not saying PSC is no good, but the light to touch steering may have been the problem. My CJ7 is lighter to touch and drives straight so maybe a wheel base/ weight/ etc issue.
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Old 11-29-2021, 06:40 PM   #11
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Re: Solved

Quote:
Originally Posted by chris989 View Post
Hello all,

Finally after years of constantly fighting the constant steering required to stay straight on the highway I puller the PSC box,

I bought a new Lares 11263. I used Lares on some other builds and always perfect.

I have put a ew hundred miles on the new box (210 T-bar) and the truck drives like a new truck. I can not put into words how much better it is. I had the PSC box out and bench adjust several time and then fiddled with even more after install and never any luck.

Not saying PSC is no good, but the light to touch steering may have been the problem. My CJ7 is lighter to touch and drives straight so maybe a wheel base/ weight/ etc issue.
Nice, informative follow-up.
Thanks....
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