Jump to content

rsb502

BMT VIP
  • Posts

    4,321
  • Joined

  • Last visited

  • Days Won

    17

Posts posted by rsb502

  1. We had some pretty aggresive wear on our school buses here too, when I first started helping with work on em I couldnt even drive yet and they were std 16x7 rears, a few years later and heavier diesel buses with full underfloor storage and pretty much everybody stepped up to larger fron and rear shoes, 8.6" rear shoes wear pretty well, figure on changing them once a year with a long high capacity route, year and a half to two years on a short route or low ridership. All of the buses here are 84 or 90 passenger, most are Blue Bird or Thomas with 13,200-14,600# steer and 23,000# drive axles 16 ply 11 R22.5 tires and 8.3 Cummins 250-300hp power, since the egr and scr changes the forward engine buses can only fit the 6.7 Cummins but they order them in at 280hp with 3000 series allison 5 speeds so they do pretty good. They had tried to push air disk at the Thomas dealer a while back but there was no state rule on them and the cost was prohibitive for an owner operator.

    • Like 1
  2. as above if everything works right and you dont have a headlight that is shorting inside it will probably be a ground, unplug the headlight bulbs one at a time and see if it goes off that will narrow it down to that bulb or that side of the harness. the cab lights sounds like a relay or fuse, you stated only two work, is it the outside two? if so the center three are on the parking light harness and run thru the parking light relay and fuse so if you have park lights they should be on, if the outside two are out they are on the clearance light circuit and have a seperate fuse and relay, there should be fuses on the firewall near the steering shaft and in the dash on the right side. If you have a wiring issue up front in the parking light harness that could also kill the center three cab lights and make the high beam indicator stay on.

  3. ok the valve that is leaking air is the spring brake quick release valve? this would be the valve that has air lines going to all of the spring brake chambers to the emergency side, is that correct? if so, you may jut have a bad brake chamber andn your service side is bleeding into the parking side, try removing the service lines from your chambers and release the parking brakes, with the parking brake valve pushed in and no service application made there shouldnt be any air coming out of the chambers where you removed the service lines, mif there is that brake chamber is bad.

  4. There have been on other guys on here that really liked the 445 too, seems to be a good spec, just gotta get the rpm in the sweet spot and with an eaton or Mack 13 or 18 you can split a gear and keep it there easier than a 9-12 speed but with the m drive they say you can get better mileage. If you could get em to put in an Allison TCS10 you'd be set, that torque converter would make it niiiice.

    • Like 1
  5. You have to take tire size, transmission ratio and gear ratio into account to get your cruise rpm. I run 1450rpm at 70 in the RW with 11R24.5 tires and 3.65 rears. With the E9 that's about the best economy, somewhere from 1400-1500rpm, any less it lugs and uses more fuel, still pulls hard just uses more fuel to do it. I watch the boost and pyrometer more than anything and rolling into the throttle under 1400 you can watch it climb, around 1500 the pyro stays under 900, its burning the fuel more efficiently because it has more air.

    • Like 1
  6. Probably steers like a goldhofer or military HET trailer, the front axle is rigid all others turn in increasing angles. The M1000 HET trailer has 5 axle lines with 4 wheel bogies on each side and the 4 rear lines then a max of 5 degrees, 15 degrees, 30 degrees and 45 degrees. Biggest reason I remember is that's the speed limits on the CTI settings too for the M1070 tractor.

    • Like 2
  7. Well you get more rear wheel torque with direct drive, any overdrive reduces rear wheel torque and so therefore you have a shot of best mpg with direct but the higher gears are easier to damage and you lose bottom end takeoff. Running near gross you will appreciate the lower 1st gear with an overdrive transmission and its unlikely youll ever notice much difference in mileage out of a controlled test setting. If you were running closer to 40,000-50,000# all the time a higher low wont matter as much so the direct would give you decent service. If your not set on the M Drive and want to get the best of both worlds go with a Mack 318LR or 313LR, or even an Eaton 18 speed transmission there youll get a lower low gear to get you moving near gross so you can still run the higher rear gears and when you pop it into OD your gonna really drop rpm. Have you decided against the super econodyne option? Mack has alreay done the homework if you go with the Super Econodyne Pinnacle and you should get the best possible mpg with that set up.

    • Like 1
  8. Been partial to Fontaine for a lonmg time, thats all Ive had but I hear good things about holland too. I like the ease of rebuild on a Fontaine, the jaw system is self tighteneing too, then just back the nut out on the front and give it a little more when it gets sloppy.

  9. I meant that Mack backed out without completing the project, they seem to be awful good at that lately. From what I gather the big thing about this truck is the hydraulic self leveling suspension. It is pretty neat when you look at the capabilities, the self leveling to dump feature for sure.

  10. Of course no one noted the dramatic increase in stopping power with the bed up, looks like stopping distance from 60-0 went from 300+ feet down to 2'. I'd be surprised if he wasn't laying in the road about a hundred yards in front of the truck with a red stripe behind him back to the truck.

  11. Had one in the 04 Granite I had, needed a rebuild of the reverse synchros when I got it due to others shifting to reverse before completely stopping. Mack fixed it under warranty and I never had another issue till i sold it, a friend had the same issue fixed under warranty and his went almost 600,000mi till he sold it with no other problems. They are great transmissions when they are used properly, just stop completely before going to reverse and split before you move the shifter and you'll be good. They have better gear steps than an 8LL and the multi speed reverse is awesome on a job site too.

    • Like 1
×
×
  • Create New...