22 RAM 5500 front alignment specs

[jacob302]

The outer edges of my 22 Ram 5500 with 60 inch cab to axle distance with 19.5 inch rims and Hankook tires are showing more wear than inside after 7500 miles. Truck has a flat bed on it and is used to carry a 4500 pound truck camper. Front axle weight is about 5500 pounds on CAT scale, well under max of 7000 pounds rating and is evenly distributed between each wheel. 70% of the miles are highway miles, the rest is paved roads in suburban areas. Tire pressures have always been 90 - 95 psi cold and 95 - 100 psi when running.

Does any one else have experience with 5th gen cab chassis models and tire wear. I am taking it to a good local tire shop that services truck tires to get front end alignment checked. I could not find specs for caster, camber or toe online. Does any one know what they should be. In normal driving I have noticed no pulling left or right, but on center feel is non existent since new, and others have reported this so I assume it is normal.

 

[rzr6-4]

19.5 inch rims

That's not a thing.

Tire pressures have always been 90 - 95 psi cold and 95 - 100 psi when running.

Holy s***. Remind me to never stand next to your tires. 100 is WWWAAAAAAYYYYY over inflated. I would be nervous standing next to a tire trying to air it up that high. Your truck probly rides like its made of rocks.

I could not find specs for caster, camber or toe online. Does any one know what they should be.

No toe, no camber, caster kind of depends on what tire size you are running. That said, if you are all stock, those should all be good from factory.

You should attach a pic of the tire wear so we can see what you are dealing with.

 

[tjfdesmo]

Ram tends to run way more toe-in than a straight axle should. Thuren says to aim for zero toe-in.

Per the load/inflation data it looks like you could drop your fronts to 80 psi.

 

[rzr6-4]

Ram tends to run way more toe-in than a straight axle should. Thuren says to aim for zero toe-in.

Toe is called out for 0.00 to 0.2 deg if I remember correctly. Are you saying that callout is too wide or that from factory they deviate from their own spec? If you end up on the high end with .2 deg that still isn't a lot. And on the other end of spec, 0 is exactly what you say it should be.

 

[jacob302]

I am attaching pictures as requested for both front tires.

The tires have a max rating of 110 psi, the numbers on the door jab call for 95 psi all around. I agree that lower pressure of 80 psi would also work given my CAT scale weight of 17000 pounds (5500 front, 11500 rear). Vehicle is rated for 19,500 GVWR. Lower pressures tend to increase edge wear and higher pressures center wear so would running at 80 psi make my edge wear worse. I am seeing edge wear on just the outer edge of the front tires as shown in pictures, the inside edges look less worn.

Tires are Hankook SmartFlex DH35, 225 70 R19.5, 3950 pounds max load at 110 PSI, 14 ply tread, 4 ply side wall.

My plan is to request the tire shop to set 0 toe and 0 camber. What do you all think ?

 

[rzr6-4]

Ok, I'm confused now.

(5500 front, 11500 rear)

You have almost 12k lbs on the rear axle alone? Or are you pulling a camper and you incorrectly added that weight?

is used to carry a 4500 pound truck camper.

If you have 4500lb in the bed with a rear axle weight of 12k lb, then you are severely overloaded. Tires are seeing 5750lb each, which is 45% overloaded. Your rear axle rating is in the 6000lb neighborhood I believe, so you are almost double there as well. If I am reading this right and all of that weight is on your flat bed, then ya you are going to get bad tire wear. Along with wearing out everything else in the rear.

If I am wrong and you are pulling a large portion of that weight, then perhaps something is wrong with your alignment. More clarification needed.

 

[jacob302]

The rear axle is rated for 13,500. They are duallys on the rears, each tire is rated for 3700 pounds X 4 = 14,800 pounds, I am well under max in all cases.

I am not pulling anything, this is a truck camper. Those are like big boxes, fully carried by the truck, nothing in tow. This is a 5500, not 3500, big difference.

 

[rzr6-4]

The rear axle is rated for 13,500. They are duallys on the rears, each tire is rated for 3700 pounds X 4 = 14,800 pounds, I am well under max in all cases.

I am not pulling anything, this is a truck camper. Those are like big boxes, fully carried by the truck, nothing in tow. This is a 5500, not 3500, big difference.

My bad, I can't read. I thought you had a 2500 this whole time.

That said, your rounding doesn't look terrible, I've definitely seen worse. If you're already at 100psi, I can't imagine more pressure being necessary. Are the inside and outside edges both wearing quickly, or just the outside?

Perhaps someone else will chime in with their thoughts.

 

[jacob302]

I followed the advice of you all. I downloaded Thuren's specs for Ram trucks, spoke to Andrew at Thuren and he said the numbers apply to RAM cab chassis as well. I found a shop that does big rigs who could accommodate my vehicle. Their tech agreed that excessive toe in can cause front tires outer edges to wear and adjusted my alignment to Thuren's specs. Below are my before and after numbers. The truck handles better now with more on center steering feel. I increased front pressures to 100 psi cold, 105 - 110 running to minimize edge wear. ADAS was not re calibrated and the systems seem to work normally as it was before the alignment. Thanks to all for the input and recommendations.

 

[crazy jerry]

its not a bad idea to rotate tires every 5k. be sure the shop uses a torq wrench and not impact gun

 

[Sherman Bird]

The outer edges of my 22 Ram 5500 with 60 inch cab to axle distance with 19.5 inch rims and Hankook tires are showing more wear than inside after 7500 miles. Truck has a flat bed on it and is used to carry a 4500 pound truck camper. Front axle weight is about 5500 pounds on CAT scale, well under max of 7000 pounds rating and is evenly distributed between each wheel. 70% of the miles are highway miles, the rest is paved roads in suburban areas. Tire pressures have always been 90 - 95 psi cold and 95 - 100 psi when running.

Does any one else have experience with 5th gen cab chassis models and tire wear. I am taking it to a good local tire shop that services truck tires to get front end alignment checked. I could not find specs for caster, camber or toe online. Does any one know what they should be. In normal driving I have noticed no pulling left or right, but on center feel is non existent since new, and others have reported this so I assume it is normal.

If you find an alignment shop who will WORK at eliminating toe change under load, you will eliminate tire wear almost totally.

 

[vlamgat]

I followed the advice of you all. I downloaded Thuren's specs for Ram trucks, spoke to Andrew at Thuren and he said the numbers apply to RAM cab chassis as well. I found a shop that does big rigs who could accommodate my vehicle. Their tech agreed that excessive toe in can cause front tires outer edges to wear and adjusted my alignment to Thuren's specs. Below are my before and after numbers. The truck handles better now with more on center steering feel. I increased front pressures to 100 psi cold, 105 - 110 running to minimize edge wear. ADAS was not re calibrated and the systems seem to work normally as it was before the alignment. Thanks to all for the input and recommendations.

View attachment 552398

My guess is that you have an Isata 5, probably an FW. So thanks for posting. Did your tech say anything about the caster adjustment? I ask because the Workshop Manual specifies this as possible but my 5500 Isata 5 28SS is not fitted with the same caster cams that the 3500/2500/1500 received and so caster cannot be adjusted. This also means camber cannot be adjusted either as the 2 are related and there is also no camber adjustment.
Also your tech did this alignment with the wrong wheelbase in the setup which means your rear settings are wrong. My guess is that the thrust angle is slightly larger than your sheet reports. The largest wheelbase in the Hunter set up is 210" but your wheelbase is closer to 217".

 

[tjfdesmo]

The first post says it's a 60" C/A C&C with a flatbed carrying a truck camper. Even a crewcab would only have a 173.4 wheelbase.

 

[vlamgat]

The Dynamax RV Isata 5 series is built on a Moryde extended 5500 standard cab chassis. The WM only gives wheelbase alignment specs out to 204" which we use even though the chassis is a 217" WB. I think he gave that description just to explain his needs as these Super C Class RVs are very rare.