kjansen
Well-known member
While winterizing and checking over the 5er, I notice cupping on the inside all four tires. Do I have two bent axles or can the wheels be aligned?
tires cupping
- Thread starter kjansen
- Start date
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To answer your question, yes you can have wheels aligned, often they bend the axles to get the desired results. Cupping on the inside can come from many factors. Alignment and suspension for sure, but tire balance (and trailer tires often are not balanced or done right) and junk tires to begin with. I would first consider miles on tires, weight on tires, type/quality of tires, and age of tires. If you take it to a frame shop for inspection, I certainly would have it loaded as you do while traveling.
Rene T
Site Team
kjansen said:
I would take it to a scale and weigh it loaded just like you were going to travel. If all looks good, then take it to a truck place that does RV axle alignment like Spencer said. I took mine to a place and they gave me a runoff of what it was before alignment and after. Mine were way out of alignment. I also had severe tire wearing. That was 3 years ago and my tires are wearing perfectly now. 2 of them have over 7000 miles on them and the other 2 have 4500 miles on them. Make sure to get them balanced also.
Gary RV_Wizard
Site Team
Cupping indicates the wheel is bouncing or wobbling as it rolls, producing an intermittent wear pattern. It can be cause by bad wheel balance, a bent wheel or hub, or an extreme alignment issue. Worn shocks too, but that's rare on trailer tires.
Just to be sure we are talking about the same tire condition, your tire shows wear only in spots and not continuously along the surface? The uneven wear is the distinction between cupping and feathering or edge wear.
This article shows what cupping looks like:
https://www.utires.com/articles/back-tires-cupping/
Just to be sure we are talking about the same tire condition, your tire shows wear only in spots and not continuously along the surface? The uneven wear is the distinction between cupping and feathering or edge wear.
This article shows what cupping looks like:
https://www.utires.com/articles/back-tires-cupping/
kjansen
Well-known member
They are cupping and were balanced when new. I have the exact same tire on my pickup and they are in great shape after 5-6 times more miles on them. The shocks are 2002 original and I have thought about replacing them. Right now I am checking into the cost of re-alignment verses new axles. These are 7,000 pound axles on a 35 foot 5er. I will wait til spring to have it weighed unless I leave Minnesota for wartmer climates this winter.
Gary RV_Wizard
Site Team
Could be worn spindles or bad bearings too. If the wheel wobbles as it rotates, the tire will cup.
A bent axle usually causes feathered edge wear due to a wheel camber problem (the axle bent up or down). Either inner or outer edge wears, but evenly. Trailer axles don't develop a toe in/out problem like the steer axle on a car or truck - they are fixed in place. The axle has to get bent forward or backward at the middle to cause toe problems. Rarely would the entire axle get far enough out of line to cause wheel hop. I'm betting on bearings, or bent hub/spindle. An alignment shop can tell you if the axles are a problem, or you can DIY an axle measurement to determine if they are correct or not.
This article should help.
https://www.centrevilletrailer.com/how-tos/trailer-axle-alignment-trailer-tire-wear/
A bent axle usually causes feathered edge wear due to a wheel camber problem (the axle bent up or down). Either inner or outer edge wears, but evenly. Trailer axles don't develop a toe in/out problem like the steer axle on a car or truck - they are fixed in place. The axle has to get bent forward or backward at the middle to cause toe problems. Rarely would the entire axle get far enough out of line to cause wheel hop. I'm betting on bearings, or bent hub/spindle. An alignment shop can tell you if the axles are a problem, or you can DIY an axle measurement to determine if they are correct or not.
This article should help.
https://www.centrevilletrailer.com/how-tos/trailer-axle-alignment-trailer-tire-wear/
If all four are wearing on the inside edge it is likely from the axles being overloaded. The weight bends them so the top of the tire is tilted inboard a little and that makes them ride on the inside edge of the tire. If just one tire was showing that wear it would be much more likely a bent axle.
2002 fiver? Have you replaced the plastic spring eye bushings ever? Like others have said, there are a myrid of things that could be contributing to the issue. Before you spend any time on alignment be absolutely sure all of the suspension is up to snuff. Spring eye bushings, springs, hangars, wheel bearings. Once you have fixed all the worn out parts head to the alignment shop.
steveblonde
Well-known member
trailer axles are rarely straight and can be straightened - look for a standens or associate close to you they will do it npkjansen said:
FastEagle
Well-known member
- Joined
- Jan 12, 2010
- Posts
- 647
kjansen said:
See page 20 in the reference.
https://www.keystonerv.com/media/9141971/keystone-owners-manual-2019.pdf
Gary RV_Wizard
Site Team
Kjansen says the tires are cupping, not wearing evenly along the inner edge. Different symptoms.
