Had our Class C aligned with more positive caster.

[2kGeorgieBoy]

Today I took our Ford E450 based RV to a truck alignment shop in Colorado Springs. They increased the positive caster from about 3.5/4.5 to just shy of plus 6 degrees. I drove from there to Pueblo on I25 and then back to Canon City on Rt 50 and on to Westcliffe via Rt 96. What a difference it made. It took me a while to readjust to the difference in handling and stability. Although the unit only has slightly over 30k miles on it, I'm going to replace the OEM shimmy shock and after market Monroe Gas Magnum shocks with all Bilstein shocks that I have on order. We're planning a trip back home to Maryland this fall and I'm hoping these upgrades will make for a relaxing trip. I've read a lot of positive comments about this caster change and so far I have to agree.

 

[youracman]

Thanks a TON for this post, 2kGeorgieBoy.  Would you mind posting the name of the shop and what the cost was?  Also, if they had to install the eccentric parts to get the caster you wanted, did they have the parts on hand?  The shops I have talked to seem to want to tell me what I want.....so it's a "take what we give you" deal.  The Springs ain't all that far away.  :^)  TIA

 

[blw2]

yeah, I too am interested in this.

I took my 2013 model E-450 to a truck alignment shop in Orlando (Josams)
They "explained" that the caster is a trade-off against camber.... as in any more caster then I would have a problem with camber (bump steering, and so on...)

I don't remember off hand where mine landed, but it was nowhere near that high. (caster)

I will say that I saw a a minimal / marginal improvement overall in handling form the alignment, and along with proper tire inflation i really don't have what I would describe as a problem now.

so 2kgeorgieboy, do you have a complete report of your numbers?
I'd love to know where you camber numbers landed

 

[sadixon49]

I would also like to here more details. How old is your E450? Mines a 2016 and it seems Ford has made some changes. Most people say the new ones don't respond as well to +caster, but I'm not sure.

 

[Olustee bus]

Everything I hear says adjust to 5.5. I am gonna do that on my 2006 conquest.

 

[Buddy110]

You really don't want positive caster, you want neutral or slightly negative caster.  6 degrees of positive caster will cause excessive tire wear.

 

[2kGeorgieBoy]

Buddy 110...I think you are refering to camber where the top of the wheel leans in or out, in relation to the vehicle, causing inside or outside edge wear. (A problem with the early model Corvairs with swing axles, which was corrected when the 2nd generation was equipped with fully independent, similar to the Corvettes).  Caster works with the steering axis, kind of like having a bicycle with a longer or shorter front fork. This causes the bike to be more stable, longer fork, or more "twitchy", shorter fork (my interpretation of caster and a bicycle fork).

 

[MYRV2]

yeah, I too am interested in this.

I took my 2013 model E-450 to a truck alignment shop in Orlando (Josams)
They "explained" that the caster is a trade-off against camber.... as in any more caster then I would have a problem with camber (bump steering, and so on...)

I don't remember off hand where mine landed, but it was nowhere near that high. (caster)

I will say that I saw a a minimal / marginal improvement overall in handling form the alignment, and along with proper tire inflation i really don't have what I would describe as a problem now.

so 2kgeorgieboy, do you have a complete report of your numbers?
I'd love to know where you camber numbers landed

that's because they are too lazy to change out the cams...a good aliegnment shop has them on hand and can try different one to get it right..

 

[MYRV2]

6 degrees is target for spot on...put about 1/2 degree lead for road crown...

 

[Buddy110]

that's because they are too lazy to change out the cams...a good aliegnment shop has them on hand and can try different one to get it right..

You are correct. I read it wrong.. My bad

 

[MYRV2]

Everything I hear says adjust to 5.5. I am gonna do that on my 2006 conquest.

if you're doing it yourself...you'll most likely need cams...I never been able to get 5.5 with stock cams... but you might get lucky...

 

[MYRV2]

I make my classs "C" handle and ride real good... sumos in the rear... or shorter springs in the front...also toe in is major...

 

[2kGeorgieBoy]

To answer some of the questions people had...

First off, I'd like to say that my positive impressions of the changes in handling made by the caster change are based on driving a total of probably 100 miles. From the start. the steering felt "tight", kind of like everything had been tightened down, no perceptible play in the steering. I realize things weren't "tightened" up but that is the best way to describe it. Driving felt like you were sitting still and turning the wheel,  that kind of tight. A couple of times I was passed by "big-rigs" hauling trailers and tankers and I felt none of that lane changing push you normally get from the wind they are displacing. Coming up through the "Hard Scrabble" area of the Wet Mountains on RT96, the RV tracked and steered like our 2015 Sorento does. To me it was amazing. It will be a while before I can get more miles on our RV, but I will be sure to give an update. Right now, "I'm a HAPPY CAMPER!'

Our RV is a 2000 Georgie Boy 31' Maverick on a Ford E450 Super Duty chassis with the V10. No slides.

The place I took this to in Colorado Springs was TCI (Tire Centers Inc.) They are located at 3428 Astrozon Blvd just off of South Academy. Phone is 719-632-4300. Ed was the tech that aligned it and has 30 years of experience. He was very aware of the increased caster fix for Fords as was Shaun, one of the managers. I had no trouble "convincing" them what I wanted.

I won't list cost as I'm not sure if it was or wasn't a little high. It did include both a 2 1/2 degree and a 3 1/4 degree bushing.

I will say that I had the unit aligned back in Jan 2014 when we first bought it. Cost was a lot less then but they were recommended by Camping World of Fountain (good or bad, depending on your opinion of Camping World... LOL), so maybe I was given a break and, of course, a lot of prices have escalated in the last 2 years.

Final specs are: Camber is 9/16 degree left & 15/16 degree right; CASTER is 5 and 29/32 degrees left & 5 and 29/32 degrees right; Toe is 0.00" left and 0.00" right. Camber and Toe are well within the specs and Caster is also with Ford wanting between 1 and 3/4 degree and 7 and 1/4 degree. I know Caster is usually set slightly different left to right but I'm happy the way it is.

As I said before, I'm going to change out all four shocks and the shimmy shock with, what I consider MUCH higher quality, Bilsteins. Hope to see more improvement here in overall road feel, getting rid of a lot of the wallowing and the hopping on rough roads (including some parts of !25), I experienced.

Right now, I feel this was money well spent......Disclaimer..Your results, overall experience  and satisfaction may vary. Don't blame me....LOL!

 

[blw2]

thanks for that
very interesting!
just for discussion sake, here are my "after" numbers when I had mine aligned last year
                      Left          Right
Camber        +3.0            +3.5
Caster            +2.45        +3.15
Toe In                  +2.2

I'm assuming that if my bushing were to be turned for more + caster, my camber numbers would approach zero..... like 2KGeorgieBoy's did.  Is that correct?
So with your camber numbers near zero, you didn't notice a bump steer problem?  Might be that 100 miles just wasn't enough to set up the right bad conditions for it???.... or maybe it's just not a real concern???
  (The only think I know about it is that this is what the guys at Josams said I would get into this problem (bump steer) if they went for any more +caster..... and I can say that I have experienced this in my pickup truck.... but only very rarely when the speed is just right and i hit a bump in the road while in a curve..... the planets have to be aligned just right in my truck, but when it happens it'll wake you up!!

 

[sadixon49]

The typical truck alignment shop is hard wired to align to specs that produce the least tire wear. On commercial over the road vehicles, tires are the second largest expense, after fuel. It's hard to make them understand that my tires will rot off, long before I wear them out. If I get 50K miles in 10 years I'll be lucky. In that situation, camber is the least your alignment worries. It's caster, followed by toe-in, with camber a distant third.

 

[MYRV2]

thanks for that
very interesting!
just for discussion sake, here are my "after" numbers when I had mine aligned last year
                      Left          Right
Camber        +3.0            +3.5
Caster            +2.45        +3.15
Toe In                  +2.2

I'm assuming that if my bushing were to be turned for more + caster, my camber numbers would approach zero..... like 2KGeorgieBoy's did.  Is that correct?
So with your camber numbers near zero, you didn't notice a bump steer problem?  Might be that 100 miles just wasn't enough to set up the right bad conditions for it???.... or maybe it's just not a real concern???
  (The only think I know about it is that this is what the guys at Josams said I would get into this problem (bump steer) if they went for any more +caster..... and I can say that I have experienced this in my pickup truck.... but only very rarely when the speed is just right and i hit a bump in the road while in a curve..... the planets have to be aligned just right in my truck, but when it happens it'll wake you up!!

not to get flamed ...but.... those numbers are horrible.... way too much toe for a twin I beam...and half the caster....but probley perfect for mall crawling

 

[MYRV2]

The typical truck alignment shop is hard wired to align to specs that produce the least tire wear. On commercial over the road vehicles, tires are the second largest expense, after fuel. It's hard to make them understand that my tires will rot off, long before I wear them out. If I get 50K miles in 10 years I'll be lucky. In that situation, camber is the least your alignment worries. It's caster, followed by toe-in, with camber a distant third.

camber is easy to achieve with the right cams...most alignment shops carry them in stock..most are first to tell you that that's the most you can get with out something bad happening... but what they are really say'n is it's a PITA to do it riaght and if you don't already know better.... this is all you get

 

[MYRV2]

the problem with twin I beam is the camber is constant changing with every bump...get the caster and toe right and the rest will follow

 

[William52]

not to get flamed ...but.... those numbers are horrible.... way too much toe for a twin I beam...and half the caster....but probley perfect for mall crawling

  The toe I hope is a typo? Very bad if true. The more caster you have the more the camber changes on turns. Look at a Benz or BMW with the wheels turned. Caster spec could be 3 to 5 degrees, more the truck tends to want to go straight down the road and a little more 1/2 degree on the right helps with road crown. So is 3.0L and 3.5R good yes 4.0R and 4.5R better wants to go straight . Any thing more than .75 from one side to the other could PULL. No one wants to fight a pull for 200 miles.  Blw2 your toe is way off! camber/ caster is ok. BTW I have done Hundreds of alignments mostly cars and light trucks but the geometry is the same.    I messaged you MYRV2?

 

[William52]

You really don't want positive caster, you want neutral or slightly negative caster.  6 degrees of positive caster will cause excessive tire wear.

  Caster is not a tire wearing angle  o caster would not be good. You are thinking camber I hope.