Normal or trouble brewing?

[PrevostNewbie]

That's not how auto slack adjusters work, you might have a bad one.

[Ck2hans]

Mark:
Other than the passengers side dual my temps on all the wheels are similar to yours. Interesting how the tags run hotter than the rest.

[Fratto]

Thanks Chuck ... Its good to know.

[Coloradobus]

Have you checked your caliper piston boots for integrity and piston lubrication. If a piston is sticking, adjusting slack adjuster wont help. My 2 cents. Im assuming like our former 2000 Marathon H, you have disc all way around

[Ck2hans]

Jim:
I do have disc all around. Calipers were rebuilt about 2 yrs ago with new pads, coach is kept in a climate controlled garage so rust/rot of caliper pin/boots is unlikely although I do have that on the radar and will be checking it out. Biggest obstacle at this time is finding time to do it. Don’t have any trips planned anytime soon so it’s on the get around to it list right now.
Thanks for the thoughts/input

[Ck2hans]

UPDATE:

Pulled drive axle duals off on the passengers side after driving aprox 50 miles to get them up to temp. Visual inspection showed no signs of dragging, released the parking brake and was able to turn the axle by hand without any effort indicated no dragging.
Just drove from Fl to Al on hot sunny day, TPMS Showed average temps of 115 tp 120 BUT passenger inside was indicating 132. When shooting the tires with a thermal temp gun ALL tires were reading between 118-122 deg. IAs noted previously I have swapped the TPMS monitor’s around to see if one was out of calibration, but no matter what sensor I installed on the passengers inside dual they alll showed a higher temp on that tire.
Not sure what to make of this, I will continue to closely monitor this with the thermal temp gun

[Fratto]

Interesting. I have no idea what might cause that. Anxious to hear if others might solve the puzzle.

BTW, my drivers side converter rear mud flap was failing so I ordered one from Prevost. I forgot that the Prevost flap on the drivers side is very short ... just comes to the bottom of the muffler. The converter flap was within an inch of the ground with a heavy weight on it as well. It seems odd that Prevost would design, stock, and sell a short flap for the drivers side and a long one for the passenger side without a very good reason. I am wondering about air flow in that area. So I installed the Prevost short flap and will see if that lowers that tag tire temperature closer to the passenger side. Also, the Prevost passenger side flap while longer than the drivers side is also shorter than the converter flap and has no holes for a weight. Installed one of these too. Leave for Michigan on Tuesday and will monitor temps. Although the ambient temps will be cooler ... stay tuned

[Ck2hans]

Mark:

Interesting you mention flaps and air flow. I noticed while under the bus there is a big vertical rubber piece that's near the front of the Transmisson that has been cut to half its height and there are slots and tabs to hold a horizonal pan under the Transmisson that is not there. Starting to wonder if that's affecting air flow enough to cause my issues.
On another air flow issue, I have the Centermatic balancers on my coach and it is a large metal disk that fits between the inner and outer duals. Considering the inner dual is a steel rim I wonder if the balancing disc is holding the heat in more on the inner wheel. Question is why not the same on the driver's side?

Chuck

[Fratto]

Good Morning

OK, I have driven from DFW to Nashville and while the ambient temps are somewhat lower, the tag tires definitely run cooler with the shorter unweighted Prevost flaps. Before the tags were in the 130 range after a couple of hours. Now they are in the 118 to low 120 range. After 2+ hours, short stops will still raise temps to the high 120's. A longer stop at end of day with engine on high idle will still raise temps to 140s. At this point, I am assuming that the engine bay is heat soaked at the end of the day and the tag tires pick up this heat with out air flow from the moving coach.

I have asked around here in Nashville and no one really knows what temperature the tires (or brakes) normally run. I did run across a gentleman with a 2017 H and he monitors the tire temps using the Prevost system built into his dash. He says that his tires including the steers routinely run in the 140's while driving ... only one data point, but good to know.

Also, had Nashville check out the tag brake caliper. Learned a couple of things. 1) Somewhere in the late 90's (I think) Prevost started to change from Rockwall to Bendix brakes. They have seen coaches with different brakes on each axle! In this case, at least on the tags, I have Rockwall. 2) Rockwall brakes do not like grease. If there is too much, the mechanism will move in to apply the brakes fine but will hang on release. Someone put way to much grease in mine so they took out as much as they could. Said that I should be fine now. Heading on to Michigan in the AM and we will continue to monitor.

[RichardE]

Mark,

Bus Grease Monkey has done a handful of videos on those Rockwell/Meritor brakes on Prevosts. Might be worth watching.