Air Suspension Question

I have some questions with regards to the air suspension on my tractor. Ive been having a pretty rough ride the last 2 loads. I attributed this to I70 and I 65 from ohio up to chicago. Plus it was a heavy beer load with cases up front and a row of kegs on the rear trailer axle. I didnt notice anything on my suspension for the drive tires or the trailer so i chalked it up to Indiana. It was fine through chicago and Milwaukee.

My next load went down to fort worth and it started out great. No issues through milwaukee and chicago suburbs. Once i got through the city on I55 it started to get bumpy again. So much so my drive camera is going off probably once an hour on a road ive driven numerous times. I stopped for the night and my post trip provided no info that would help. The next day i pretrip like a madman and come up with nothing.

Im driving along and all the sudden i notice this

gauge

My suspension load gauge is plummeting. While driving! I notice that this keeps happening when my air supply goes below 85ish. So my thought is that the airbags from my drives are deflating which is giving me a bumpy ride. My question is i dont hear any leaks. My air brake tests are fine i dont lose air pressure more than normal on the static or applied test. Can this simply be from a heavy beer load going over a rough road? Also most importantly, where does your air supply gauge hover at? Mine hits the cutout at 120 then slowly drops but the compressor doeant kick on until around 85ish. Which is when the bumpy ride really starts. Luckily im at a terminal so im going to have someone look at it tomorrow but i would appreciate your thoughts. Heres the load with the air supply at 120

Sounds like you have a slow leak on the tractor somewhere, but the compressor is keeping up fine. When you have gotten back to the truck after hometime were your air tanks empty? Just a guess unless you have been dragging around the same trailer.

My truck is an 8 series but usually cuts out around 120ish as well.

Sounds like you have a slow leak on the tractor somewhere, but the compressor is keeping up fine. When you have gotten back to the truck after hometime were your air tanks empty? Just a guess unless you have been dragging around the same trailer.

My truck is an 8 series but usually cuts out around 120ish as well.

Not sure if they were empty when i got back. When does your compressor kick on. In my trainers truck it was somewhere juat below 100 mine is always lower. I spent the whole day watching the gauge and waiting dor it to kick on but it wouldnt. I had to hit the brakes to drop the pressure a bit in order for the compressor kick in and push the air supply back up to the governor cut off.

Looks 85 to 95 on mine. My trainers truck it was closer to where cut in on mine is than 100. His truck was also an 8 series. On another note, I'm in BRF and it's gonna get into the 50's tonight.

You need to call the breakdown line and explain your issue. There are three valves I can think of which may be the culprit. I’m guessing you are idling while parked in this hot weather?

Your suspension gauge will go up and down while driving. It is also only accurate on level ground. I believe Millis uses T680's. They are notorious for small leaks. How is your seat adjusted? Good luck.

Your suspension gauge will go up and down while driving. It is also only accurate on level ground. I believe Millis uses T680's. They are notorious for small leaks. How is your seat adjusted? Good luck.

I know it fluctuates as you go down the road with bumps, braking and acceleration. But it went from 60k to basically zero. I was driving at the time so i didnt want to grab my phone and snap a picture. When i took the picture it was after pulling off the road at a rest stop and the compressor had kicked in from braking.

My seat is pretty high because of my height i know everyone here preaches to noobs to lower your seat but i really cant. Old schools method applies to my high seat for me. If you mean am i getting to the point where i lose so much air my seat drops then no.

Im way back in line at the terminal for service they said hopefully this afternoon so we shall see.

So finally gor my truck looked at on Tuesday. Small leak in one of the 4 suspension airbags. Mechanic had to simulate a heavy load in order to actually find the leak. So what was happening was while driving heavy and going over bumps one of the airbags was leaking causing my air system to slowly lose psi dropping my fifth wheel frame with it causing a much bumpier ride. Of course with my bad luck they didnt have the part so i have to wait another day to get this fixed. Talking to the mechanic theres no way to pretrip something like this because how do you simulate bumpy roads while parked. Another reminder to monitor your gauges like a hawk while driving.

You can so simulate that! Get a fat guy on top of the nose of the trailer, then have him jump up and down like Jordon!

Glad they got it diagnosed and hopefully repaired tomorrow. Should be a very fast repair.

Which shop?

Burleson. Only took about an hour thankfully. He wants me to watch closely the governor cut in in case with the leak it was damaged with the computer sensors. I have a run from ft worth up to chicago so ill watch it close and if theres any problems. I start hometime after i deliver so ill drive it up to the terminal and put another service order in. Just getting loaded now and it seems to be doing the same. My pressure was at 80ish and the gauge showed no weight. Tapped the breaks a few times and the governor kicked in and now its showing 40k... Who knows.