class c alignment questions

[PattyShipc]

I have my rig in for alignment. The tech says it's aligned to specs but it's still pulling to the left. (They already replaced a shim on one side). I read somewhere, and now I can't find it, that it shouldn't be aligned to specs...? Something about +5.5 on the right?
Can anyone tell me if my rig should be aligned to specs, or if there is some secret to aligning a class c? (It has new front tires, properly inflated in the rear...)
Thanks! I appreciate any feedback

 

[Mark_K5LXP]

Is it pulling to the left following the crown of the road (sloping to the left) or on flat roads? If it's following the crown (meaning if the crown goes to the right it pulls right too) that'd be one discussion to have but generally any pulling in either direction is not correct. There could be an issue with the rear suspension that can contribute to this so that'd be something to check.

Mark B.
Albuquerque, NM

 

[TheBar]

You might search for "alignment" from the user "Harvard". But alignment should not make it pull to the left. Dragging brakes, wheel bearings, weak springs, tire inflation, etc. even loads heavier on the left side can cause it.

 

[Kirk]

If you are using a trusted shop then ask them to test drive the RV to see what they think. There are many things that can cause such problems, ranging from alignment to suspension, to tire inflation, and several others. Have you weighed your RV to get axle weights and each side weighed? The best would be getting weights for each wheel, which there are services for. If you have the left side much more heavily loaded than the right, it may well be what is causing your problems. From RV-SEF:RV Safety & Education Foundation

• The ONLY way to properly weigh your RV is by wheel position. Your tires and wheels are the foundation of your RV, and each has a maximum weight rating. An overloaded tire (a.k.a. an underinflated tire) is the number one cause of rapid tire failure (most often referred to as a "blowout").
• It is possible to be within your Gross Vehicle Weight Rating (GVWR) and your Gross Axle Weight Ratings (GAWR), and still overload a tire at an individual wheel position.
• Unless you know the load/weight carried by each wheel position, you have no way to know the proper inflation of your tires. Improper inflation leads to improper wear, reduced life of the tire, and greater potential for rapid tire failure.

RV Smart Weigh
RV Safety & Education Foundation

RV Mobile Weigh Station​

 

[Bobtop46]

E350/E450 Handling Problems are caused by too little + CASTER

Help. I have read about the caster settings and now here is my problem. My E450 2006 model had slightly less than 1 degree of positive caster. I have installed a 3-1/2 degree bushing which gives me slightly under 4-1/2 degree positive caster. Handling has much improved, however, still some...

www.rvforum.net

 

[Gary RV_Wizard]

The caster adjustment has nothing to do with pulling left or right - it has to do with tracking straight ahead without constant correction. The recommendation to use more than the factory spec caster is a different question than your issue. The Bar gave some good suggestions, and Mark's comments re road crown are on target as well.

 

[PattyShipc]

they're driving it...hard to tell what's going on as there's a strong wind. could be effecting it

If you are using a trusted shop then ask them to test drive the RV to see what they think. There are many things that can cause such problems, ranging from alignment to suspension, to tire inflation, and several others. Have you weighed your RV to get axle weights and each side weighed? The best would be getting weights for each wheel, which there are services for. If you have the left side much more heavily loaded than the right, it may well be what is causing your problems. From RV-SEF:RV Safety & Education Foundation

• The ONLY way to properly weigh your RV is by wheel position. Your tires and wheels are the foundation of your RV, and each has a maximum weight rating. An overloaded tire (a.k.a. an underinflated tire) is the number one cause of rapid tire failure (most often referred to as a "blowout").
• It is possible to be within your Gross Vehicle Weight Rating (GVWR) and your Gross Axle Weight Ratings (GAWR), and still overload a tire at an individual wheel position.
• Unless you know the load/weight carried by each wheel position, you have no way to know the proper inflation of your tires. Improper inflation leads to improper wear, reduced life of the tire, and greater potential for rapid tire failure.

RV Smart Weigh
RV Safety & Education Foundation

RV Mobile Weigh Station​

Thanks. That's very helpful. Weighing has been on my list...I'm getting there.
Got new highway tires in the front.
Got all 4 in the rear properly inflated. It was a chore!
Now the alignment.
It's a good shop. They kept it a few days...test drove it a couple of days.
Thanks again

 

[PattyShipc]

You might search for "alignment" from the user "Harvard". But alignment should not make it pull to the left. Dragging brakes, wheel bearings, weak springs, tire inflation, etc. even loads heavier on the left side can cause it.

Yep.
The water tank is on the left.
I filled it for the alignment

 

[Kirk]

The water tank is on the left.
I filled it for the alignment

Where the problem may be is that your RV weighs significantly more on the left side than on the right. That would cause it to pull left, even if perfectly aligned. Alignment gets it to steer properly but it will not overcome problems from the suspension when overloaded or when weight is not properly distributed.

 

[decaturbob]

- weight distribution
- wind
- road condition
- and last is wheel alignment and brakes

at what speeds does rig pull to the left? Has to be an absence of wind when analyzing this.

 

[Ray-IN]

Did the shop do a total alignment or only the front wheels? This explains Alignment Specs: Thrust Angle and Setback
The tell-tale sign of incorrect thrust angle is the steering wheel bars are not level when driving a straight line. Incorrect thrust angle also causes unusual tire wear.
Our MH was out by 3/4". After correction driving is much more comfortable and I get .5 MPH increase.

 

[ChasA]

Did the shop do a total alignment or only the front wheels? This explains Alignment Specs: Thrust Angle and Setback
The tell-tale sign of incorrect thrust angle is the steering wheel bars are not level when driving a straight line. Incorrect thrust angle also causes unusual tire wear.
Our MH was out by 3/4". After correction driving is much more comfortable and I get .5 MPH increase.

Ray, don't you mean MPG?

 

[Ray-IN]

Yea, thanks. I fat-fingered that.