Tag Axle tire wear

[resullivan]

On my 2017 LADP the tag axle tire on the driver side is showing unusual wear from the outside of the tire to the first groove in the tread, (about 1 1/2"). Coach has 30K miles and all other tires wearing uniformly. Anyone else experience this issue, and or any ideas? Thanks

[drdonny]

Freightliner or Spartan?

[resullivan]

Freightliner

[Tigerfan1]

Originally Posted by resullivan

On my 2017 LADP the tag axle tire on the driver side is showing unusual wear from the outside of the tire to the first groove in the tread, (about 1 1/2"). Coach has 30K miles and all other tires wearing uniformly. Anyone else experience this issue, and or any ideas? Thanks

I would contact Freightliner in Gaffney, SC. There was a issue with tag axle alignment/ off center problems. Mine was corrected at the Gaffney service center.

[tom chelbana]

On our Essex we had almost 90K miles when we purchased new tires and the tag axle were just as good as the rest of the tires. All 8 just aged out of service. This was on a Spartan chassis. There have been Newmar owners who have had issues with tag on FL chassis and a contact with them would be a good place to check on this wear problem.
Newmar Man

[Rd1]

Originally Posted by resullivan

On my 2017 LADP the tag axle tire on the driver side is showing unusual wear from the outside of the tire to the first groove in the tread, (about 1 1/2").

Is this similar to your tire wear? this was my third set of tag tires replaced at 58k, just last October.

Did you ever had the tag axle issue examined when you purchased new?

[ptw]

Originally Posted by Rd1

Is this similar to your tire wear? this was my third set of tag tires replaced at 58k, just last October.

Did you ever had the tag axle issue examined when you purchased new?

My tag tires look new except a little wear on the outside edge of the tire. There are over 40,000 miles on my first set of tires. During my 6 month service in Gaffney (one year from build date), Freightliner in Gaffney checked the alignment and found the tag tires needed adjustment. They did alignment under warranty.

Do you keep the dump switch in the forward position for auto tag dump?

[05kstar]

Freightliner has a known axle alignment issue.Contactct Freightliner and they should make it right.R and S spring and alignment took care of a friend of mines at Freightliners expense. This shop is in Bladensburg,Maryland but there are truck shops all over the country that can handle it.

[Rd1]

Originally Posted by ptw

My tag tires look new except a little wear on the outside edge of the tire.


Do you keep the dump switch in the forward position for auto tag dump?

The tag dump is on auto. curious, why do you think the tag dump is related to the RHS outside tire wear?

Is your RHS tag tire continue wearing out on the outside edge?

[Rd1]

Originally Posted by 05kstar

Freightliner has a known axle alignment issue..

Yes, that unfortunately is a fact!!!

I was the second owner posting on this issue on this very forum back in 2016. I had 4 alignments just in the first 3 months of ownership at different freightliner dealers and one where newmar used to have all their alignments performed.

Every one of those attempts indicated alignments were off. They supposedly aligned and centered every thing perfectly. Only to find out a couple of weeks later or a month later at the next location, the alignments were not in spec.

The following year, freightliner's own engineer responsible for the tag axle along with the engineering director from Hendrickson (tag axle mfr) worked on it. The tire you see above is the result of their handy work. That seems to suggest, they are not able to align their own chassis to proper specs. Hence the continued tire wear.

The tire wear was not visible to the average person's eye after their engineers worked on it, but it was present. It was confirmed by another freightliner dealer and a truck tire shop. The new tires ($1000 ea) replaced last October, already have outside edge tire wear, though not visible to the average person's eye.

[ptw]

Originally Posted by Rd1

The tag dump is on auto. curious, why do you think the tag dump is related to the RHS outside tire wear?

Is your RHS tag tire continue wearing out on the outside edge?

I took driving lessons with my wife when we bought our RV. I was outside when she was parallel parking the coach on both sides of the street. Watching the tires drag on the pavement of my brand new RV when she was backing the coach, I told the instructor that if I ever have to parallel park the RV, I would let her do it. There has to be wear on the tires from backing these rigs into campsites when they are leaving rubber marks on the concrete. I do have some wear on the outside of the tag and front tires. Not a lot. Twice Gaffney and a tire guy said it was normal wear.

[Rd1]

Originally Posted by ptw

...... Watching the tires drag on the pavement of my brand new RV when she was backing the coach,......

Twice Gaffney and a tire guy said it was normal wear.

The dragging of the tag tires while backing up is a feature of passive steer. It is common to both spartan and freightliner. If you attempt to backup right after a sharp turn going forward, the tag tires would drag on reverse. To avoid, straighten the front wheels and pull forward 2-3 ft, then go on reverse. That would eliminate the dragging issue. Nonetheless, the dragging issue does not causes the outside edge of the right hand tag tire to wear out. Backing up 100 ft or so every so often, does not cause this type of tag tire wear. Do you have a photo of your tire wear?

From wiki manuals, Here is a link to some basic alignment issues as described by Hunter. Hunter is one of the main manufacturers of alignment equipment. See page 3 and 4.

The outside edge of the RHS tag tire wear is typical of a toe-in issue (see Hunter explanation above). However, what is peculiar, the toe link on my tag axle connects both tag wheels together. It is not independent toe link, as is typical in most cars. So, if the toe is out of spec, both sides should be wearing out on their outside edge. There are a couple of scenarios to consider;

If the tag axle has a thrust angle issue (mine has had this problem). You could have one wheel close to toe spec and the other would be noticeably out of spec. Hence causing the outside tire wear. See page 5 of the above manual for a description of the thrust issue. The graphic the hunter manual shows is a positive thrust. Axle rotated to the right. Axle rotated to the left is a negative thrust angle. In my case, thrust angle is negative. In this scenario, the LHS tag tire may be in toe spec, the RHS would be way off and cause the outside tire wear.

Another scenario, could be caused by improper setting of the lock straights on the tag wheel (see pic below). The lock straights keep the tag wheels in a locked straight position when in reverse, or traveling at 'speed' going forward. The lock straight is placed on the back side of the tag wheel. If not set properly, it can push out the back side of the tag wheel, hence causing a toe-in condition.


Paul, this notation that the tag wheels dragging during the backing up does not add up to the RHS tag tire wear. Below is a list of some of the owners who had mentioned their RHS tag tire wear over the years. They are only 2016 and 2017 freightliner units. I have not heard anyone with spartan or freightliner 2018, 2019, 2020 or 2021 make any such complaints. Maybe they will opine if they are out there.

2017 DSDP post#1 and 13
2016 DSDP
2017 DSDP post#5
2016DSDP post #17
2016 VTDP post#3
2016 VTDP post #32
2017 DSDP post#8

[sramer]

Originally Posted by Rd1

The dragging of the tag tires while backing up is a feature of passive steer. It is common to both spartan and freightliner. If you attempt to backup right after a sharp turn going forward, the tag tires would drag on reverse. To avoid, straighten the front wheels and pull forward 2-3 ft, then go on reverse. That would eliminate the dragging issue. Nonetheless, the dragging issue does not causes the outside edge of the right hand tag tire to wear out. Backing up 100 ft or so every so often, does not cause this type of tag tire wear. Do you have a photo of your tire wear?

From wiki manuals, Here is a link to some basic alignment issues as described by Hunter. Hunter is one of the main manufacturers of alignment equipment. See page 3 and 4.

The outside edge of the RHS tag tire wear is typical of a toe-in issue (see Hunter explanation above). However, what is peculiar, the toe link on my tag axle connects both tag wheels together. It is not independent toe link, as is typical in most cars. So, if the toe is out of spec, both sides should be wearing out on their outside edge. There are a couple of scenarios to consider;

If the tag axle has a thrust angle issue (mine has had this problem). You could have one wheel close to toe spec and the other would be noticeably out of spec. Hence causing the outside tire wear. See page 5 of the above manual for a description of the thrust issue. The graphic the hunter manual shows is a positive thrust. Axle rotated to the right. Axle rotated to the left is a negative thrust angle. In my case, thrust angle is negative. In this scenario, the LHS tag tire may be in toe spec, the RHS would be way off and cause the outside tire wear.

Another scenario, could be caused by improper setting of the lock straights on the tag wheel (see pic below). The lock straights keep the tag wheels in a locked straight position when in reverse, or traveling at 'speed' going forward. The lock straight is placed on the back side of the tag wheel. If not set properly, it can push out the back side of the tag wheel, hence causing a toe-in condition.


Paul, this notation that the tag wheels dragging during the backing up does not add up to the RHS tag tire wear. Below is a list of some of the owners who had mentioned their RHS tag tire wear over the years. They are only 2016 and 2017 freightliner units. I have not heard anyone with spartan or freightliner 2018, 2019, 2020 or 2021 make any such complaints. Maybe they will opine if they are out there.

2017 DSDP post#1 and 13
2016 DSDP
2017 DSDP post#5
2016DSDP post #17
2016 VTDP post#3
2016 VTDP post #32
2017 DSDP post#8

Ahhh, the Tag steering locks! Someone that knows them and maybe you can help! I have a 2019 London Aire that I have had an issue since new. It has been to 2 freightliner dealers at least 8 times, had 2 alignments done and now Gaffney wants me to make a 4200 mile round trip for them to look at it.

The problem is it that wanders back and forth requiring constant steering correction depending on the crown of the road. I have played with the Tag steering locks because it is visible to the naked eye when they are locked, the left Tag tire is toe'd in and the right straight.

When I put a long straight edge across the drive tires and measure the front and rear of the tag tire, the left Tag is toe'd in 1/4" and the right perfectly straight. (The Tag also sets off center 1" to the left compared to the drive axle)

With my symptoms, it would make sense with the Tag locks being out of adjustments. When I am on a fairly flat road I get more of the wandering. Logic says if the Tag is toe'd in on one side it is going to push the rear in in that direction.

I have played with the lock adjustments and it has actually made a vast improvement. My question, is there a published adjustment procedure for the steering locks or maybe you have personal knowledge of the procedure.

I have search and searched on line and have not been able to find anything and would appreciate any help you might provide.

[Rd1]

Originally Posted by sramer

London Aire have had an issue since new. It has been to 2 freightliner dealers at least 8 times, .

If there is an issue, it is hard to expect freightliner or their dealers to tell you about it. At least from the fan housing frame issues, etc. , that appears to be their approach. If you wish to learn more about your alignment issues, I suggest finding a competent (independent) alignment shop and be involved with it. Don't just drop the coach and p/u, be there for the alignment. Do you have your alignment printouts? It helps to see what the alignments were and what was changed.

Originally Posted by sramer

The problem is it that wanders back and forth requiring constant steering correction.

The toe issue may contribute to wandering, so do other alignment problems. With a tandem axle in the back (drive and tag), it is essential both of these axles to be pointing in the same direction. If the scrub angle is out of spec, that too can contribute to the wandering. Please see pg 15 of the above linked doc from Hunter for trouble shouting and L/R pull. I have had this issue from day one. Even had a test drive at Newmar with their reps and a freightliner rep (Mr. Chassis guy). The pull was observed and documented. They like to blame CD or “your” imagination. However, if the rear axles are pointing in different directions, that would cause alignment/handling issues.

Originally Posted by sramer

(The Tag also sets off center 1" to the left compared to the drive axle).

When you had your alignments performed, was this offset taken into account? If not, the alignments were bogus (toe and thrust setting for most if not all axles would be off), no matter what the printouts say.

Originally Posted by sramer

I have played with the lock adjustments and it has actually made a vast improvement. My question, is there a published adjustment procedure for the steering locks or maybe you have personal knowledge of the procedure.

Great, you have done some testing, thats the only way you are going to find out what the issues are. A few items to consider. The lock straights have small adjustments on mine. I do not know if yours may be the same, or what may have changed? Using your own logic of common sense, the 'lock straight' suggests the components are designed for keeping the wheel straight. Using them for toe adjustments for your testing purposes is fine. They are to be set once all alignments are good, then set the locks accordingly, to keep the wheels straight. However, if they are used for toe changes, the turning radius will be effected. I have checked mine on an alignment rack using 'turn tables', with lock straights released, the max turn is actually only 8 degrees, ea side and not the 12 as advertised, at least on my unit.

To better understand the issues, a complete and ACCURATE alignment data is essential to diagnose the problem(s).