We made the 800 miles from CO to Iowa without any trouble. OK... the turn signal stalk came off in my hand midway through the trip, but that's an easy fix. But, we do have some serious vibration issues now, and need to figure it out. I put on new steer tires right before the trip and didn't have them spin balanced, since I have Balancemasters that came with the coach. Their documentation says not to spin balance tires, and none of my other wheels have ever had weights on them. But (mostly) between 60mph and 70mph there's a very distinct vibration that wasn't there before this trip.
To add other variables, I also put a new brake drum on the RR and re-packed the bearing, etc. and also put new shocks all around.
Any suggestions?
Thanks,
Brian Brown
presently in Iowa City, IA (and sweating!)
Did you have the drum turned before installing? Was it mounted to the hub when it was turned?
Is it possible you warped a hub by overtightening the nuts, or not tightening them in the proper order?
One thing you can do is jack up each wheel just barely off the ground and spin it and watch to see if it's out of round, wobbles, etc. Can do this on the front, hard to do on the rear, though.
craig
Hey Craig:
The drum was brand new. Do they have to be turned and/or balanced when new? I hand-torqued the lug nuts on all wheels, except LR which I didn't touch.
I guess I should check the axle I repaired to see if I messed something up doing the bearings. I can also get the fronts up and spin 'em.
Thanks,
Brian
As to brake drums, a quality drum will have evidence of it being balanced before hand-you'll see some grind spots on the edges removing some of the metal to make it balance out-sometimes even welding on additional weights if it is really bad. If you don't see any evidence of these balancing techniques, maybe you have a cheapo brake drum that no matter what balancing methods you use, you'll never get the drum/wheel/tire combo balanced.
Through my 21 years of over the road driving with 1.3 million miles of driving my own truck, this is what I have learned. Aluminum wheels balance the best since they are made from one piece and are then turned to shape-rather than the steel wheel that is two piece welded together. Then when mounting new tires, ALWAYS have the tire/wheel spun balanced. I'd rather have some stick on weights (clip on weights don't work with aluminum-they usually fly off with not to good results) showing on my polished wheels, then the balancing problems that could happen. I have tried Equal-which is the powder you put inside before mounting the tire; I have tried balancing rings with Mercury in them (just about useless). What works the best is the Centrimatics with the ball bearings in auto trans fluid.
To recap-make sure you're using a new brake drum that has already been balanced; when mounting new tires, have them spun balanced (including the rears); use Centrimatic balancing rings on the front AND back. You'll have a silky smooth ride-I know, I've had comments on how smooth my bus rides-and this from mechanics that have worked on 100's of buses!
And to top it off-make sure you're running the proper tire pressure for the weight of your bus. Just don't run the max on the side of the tire-it makes the bus ride like a fork lift. For instance, I only run 90psi in my tires-which is proper for my wieghts. Good Luck, TomC
I gotta go right to the new tires or the balance product. What brand of tire did you buy? A tire that vibrates on a commercial vehicle has internal problems and needs to be removed immediately. A balance magician is just hocus pocus and so are wheel weights. You have a 100lb tire that is carrying 6000 lbs. How could a 2-6 oz weight ever make a difference to anything other than some tire dealers bottom line?
If you bought a quality tire I will guess the Balance Master got some moisture and froze in a position that helped neutralize the old tiire and is affecting the new tires. If the new tires are round, throw away the Balance Master and the issue should be gone. If its a tire, make them give you another one, a new tire that needs balance is junk. A new tire that vibrates is junk . I guarantee if you put a Bridgestone on it and follow the mounting directions you will never need to balance. If you buy an inferior tire and pay to balance it, you will have spent as much money as the Bridgestone and still have an inferior tire. I don't have to blow the horn for Bridgestone although I could, as I have used them since 1970 on my truck fleet. I will let Peterbilt and Kenworth have that honor as its the tire they ship all new trucks out the door with, and has been for a number of years.
Brian,
Yes, a new drum should be mounted to the hub and then cut on a lathe. New pads should then be matched (standard size on new drum).
Make sure you mark the drum and the hub alignment, so that when they go back together on the bus, they are in the same orientation to each other as when they were cut. I use a center punch to mark them, and then paint the marks.
There's a shop here in Bloomington that can cut your drum if you want to do it while you're up here. Would cost you new seal, plus their time to turn it, and your time to pull it and take it down to them. I can probably assist you if you want to do it yourself, or I bet they could get you in if you called them and made an appointment. They do good work.
craig
My 2 pennies!!! Balance masters have a document that clearly reads all tires should be balanced before using their products. Their balancers are designed to keep tires balanced. They only balance up to a certain percent.
--
BILL
I have had it confirmed.....by a freind in the commercail tire industry.......
THEY AINT ROUND ALOTOF THE TIME.....and sometimes even when round are not in ballance.
I have had vehicles with high end tires that vibrate even when ballanced......trued them...vibration goes away.
this has been on steel wheels and Alcoas..
Hvae used Cetrimatics on both my 04 and my Dad's 08 with noticable increase in ride quality.
on the MC-8 I used Dynabeads also with notiable increase in ride quality.
My opinion...those who don't ballance.......just cheap...or can't notice certain frequncy vibrations.
I don't know of any charter operators ( ones that have more than just a few buses) who don't ballance
Also do not know of any "local" nationwide trucking outfirts that don't at least ballance the steer tires, if not all the tractor tires.
Most don't ballance the trailer as the cargo doesn't give a rats rear how it feaels and that vibration is very dampened by the time it makes it to the cab
Heck they ballance airplane tires
Thanks for the info, folks. There's a shop here in I.C that does dynamic wheel balancing, along with laser alignment. I've had issues with front tire wear in the past, so I'll try to get it in this week before heading north. I only really have two days up in the Twin Cities, so I don't want to push it with the work.
Thanks,
Brian
Running too high a PSI or too low can cause funny wear.
I had sometires once that were designed for Local/Regional duty (goodyears)......crappy wear patterns changed to Highway rated ( michilin) and put Cetrimatics on at the same time....wear gone and vibration gone.
Brian - if you have your IR thermometer with you, you may want to check your hub temps after a decent run to rule out any of the above, before spending too much $$$$$ on the road - HTH
Well, we did a 200 mile run yesterday with 12 family members on board (majority were kiddos... there's something about kids and busses). The ride was noticeably improved with relation to vibration... but the roads were soooo much better than the typical washboard of I-80. I'm debating whether to mess with things too much while I'm here.
Niles, I've been checking hub temps the whole trip and the rear axles are just warm to the touch... maybe 100 deg. and the same each side, while the fronts are almost cold. The left steer tire is starting to show a little edge wear on the road side, just like the old set did. I'll need to get some alignment adjustment pretty soon.
BTW, I'm hooking up with Brian Diehl, Craig Shepard, and Brian Elfert this Friday up in MN for a mini-rally. Call it The Bussin' Brians and Gumpy Rally. Pics to most certainly follow... Other non-Brian's are also welcome to show up at Fish Lake Regional Park (http://www.threeriversparkdistrict.org/parks/fishlakeregional.cfm) in Maple Grove that afternoon/ evening. Brian Diehl's place is very close to there and he has kindly offered us a spot and a 15a connection for the night.
Brian B.
what kind of tires, make and model and what preasure you running?
"I put on new steer tires right before the trip"
"I've had issues with front tire wear in the past"
"The left steer tire is starting to show a little edge wear on the road side, just like the old set did. I'll need to get some alignment adjustment pretty soon"
I'd say your right about having the alignment checked first - FWIW
I run Michelin XZE 11R-24.5 16 ply all around at 90 psi since I just have 10,500lb front and 20,500lb rear. Rides great-had them spun balanced before mounting. Run Centrimatics in the rear only-front studs are too short. Good Luck, TomC