| Author | Message | ||
| Bob Baldwin (Bob4106)
Registered Member Username: Bob4106 Post Number: 148 Registered: 10-2004 Posted From: 24.74.180.20  Rating: N/A |
I took the bus out for a trip this past weekend. (GM 4106) While driving down the interstate. I could feel the front of the bus rocking side to side. It would do so for a few minutes and stop. Then start back again. Not all the time just every so often. I do have 4 new air bags and 2 new shocks. I have not got them on yet. I would like to know if I need to look at anything else while I’m under the bus replacing those parts? Thanks | ||
| Douglas Wotring (Tekebird)
Registered Member Username: Tekebird Post Number: 319 Registered: 10-2004 Posted From: 71.59.75.212 Rating: N/A |
while your under ou should look a everything | ||
| Buswarrior (Buswarrior)
Registered Member Username: Buswarrior Post Number: 1230 Registered: 12-2000 Posted From: 76.68.135.151  Rating: N/A |
Well... don't assume it was the front only, or that the source of the roll wasn't in the rear. That being said, shock absorbers are supposed to dampen the bouncing of the suspension, shocks that aren't working will allow unusual body motions. Check that all the radius rods and sway bar are properly attached at both ends of the bus. And as tekebird suggests, everything else while you are under there too! happy coaching! buswarrior | ||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 396 Registered: 8-2006 Posted From: 207.231.75.253 Rating: N/A |
First off, BLOCK THE BUS SECURELY AT THE JACKING POINTS BEFORE GOING UNDER, or between a tire and a fender. We want you around to give us a post back on what you find! I'm pretty sure that your air ride system is essentially the same as mine, with one leveling valve for the entire front, and a leveling valve for each side in the rear, which govern the side to side level, and the rear height. What this means is that air moves back and forth, from side to side in the front, through a common pipe, and the only thing to slow a lurch down is the shock absorbers. Going over a bump in the back on one side, will make the front lean also... Please also be aware that if your bus has a driveshaft handbrake, that jacking up one rear axle will completely nullify the handbrake. So, block the front wheels well before you jack the back! HTH, and have fun, its almost springtime! George | ||
| marvin pack (Gomer)
Registered Member Username: Gomer Post Number: 216 Registered: 3-2007 Posted From: 76.4.151.87 Rating: N/A |
Bob, I had a 4106 and the tires caused some of my rocking. I ran radials on the front and bias on the rear. I changed the front back to bias and that solved a lot of problems along with changing shocks that eliminated all the problems. Just another thought.hmmm gomer | ||
| Bob Baldwin (Bob4106)
Registered Member Username: Bob4106 Post Number: 149 Registered: 10-2004 Posted From: 24.74.180.20 Rating: N/A |
Thanks, It will be like a few weeks before I can get under the bus. Just though I ask to see if any one else had the same problem. | ||
| Jim Wilke (Jim Bob) (Pd41044039)
Registered Member Username: Pd41044039 Post Number: 273 Registered: 2-2001 Posted From: 69.77.156.137 Rating: N/A |
Bob, are you saying that the rocking has not been noticed in that bus? It is normal for GMs to rock from side to side a little, as it is normal for Eagles to rock front to back. Obviously uneven pavement, side wind & oversteering can cause rocking too. Marvin, why didn't you change to radials all around? They'd give better mileage, ride & tread life. | ||
| marvin pack (Gomer)
Registered Member Username: Gomer Post Number: 217 Registered: 3-2007 Posted From: 76.4.151.87 Rating: N/A |
jim bob I COULDN"T AFFORD THEM not that I didn't want them,but when you travel and sing GOSPEL MUSIC like I still do, people think that money is given from on high and not on earth LOL. They are the ones that will pay big bucks to see their favorite team win a game or some big concert OK that is enough LOL Gomer P>S riverjordanmusic.com. I am the little person and the BEST LOOKING LOL | ||
| John Riddle (Jriddle)
Registered Member Username: Jriddle Post Number: 4 Registered: 3-2008 Posted From: 207.171.202.173  Rating: N/A |
Bob I can't comment, with bus experence on rocking, but did receive e-mail from shipping company today. I will look forward to it. I not very smart on what buses will act like, but the info above sounds good to me. I had a truck one time that had mismatched tires and the thing would not go down the road till I changed tires to be the same. I also had a pickup with problems with the suspension and had same type of problems. If shocks and airbags and alinment are bad this also could be the problem. Thanks John | ||
| RJ Long (Rjlong)
Registered Member Username: Rjlong Post Number: 1367 Registered: 12-2000 Posted From: 67.181.166.160  Rating: N/A |
Bob - I'd suggest you have the front tires checked at a competent tire shop. Since it comes and goes, it's possible you've got a tire either out-of-round or out-of-balance. FWIW & HTH. . .  | ||
| Bob Baldwin (Bob4106)
Registered Member Username: Bob4106 Post Number: 150 Registered: 10-2004 Posted From: 24.74.180.20 Rating: N/A |
Thanks for all the input. Tires where check and ok. I was thinking if the leveling valve might have anything to do with it or maybe the ride height to high? | ||
| Gus Causbie (Gusc)
Registered Member Username: Gusc Post Number: 627 Registered: 11-2005 Posted From: 70.171.233.117  Rating: N/A |
My 4104 definitely bounced and swayed more after changing to radials. The air pressure in the front tires makes a big difference also. I think the swaying or rocking is normal for GM air bag systems. I call it the ocean liner effect. | ||
| Bob Baldwin (Bob4106)
Registered Member Username: Bob4106 Post Number: 151 Registered: 10-2004 Posted From: 24.74.180.20 Rating: N/A |
Not sure about being normal. I have drove other 4106, 4104 and a few other GM buses and never felt the rocking side to side before. It's not front to back or in the back, front only. I'm not sure if all the air bags on there now are even the same kind. Doug is right about looking every thing over. I was looking to see if any one had the same problem. | ||
| Gus Causbie (Gusc)
Registered Member Username: Gusc Post Number: 628 Registered: 11-2005 Posted From: 70.171.233.117 Rating: N/A |
Bob, As I said my 4104 has done just exactly as you describe from day one and did it even more after I changed to radials. Increasing the front air pressure to about 90psi decreased it a bit but I just accept it as normal now. All my front air bags and suspension bumpers are new so I don't consider mine a safety issue. | ||
| john w. roan (Chessie4905)
Registered Member Username: Chessie4905 Post Number: 959 Registered: 10-2003 Posted From: 71.58.48.5  Rating: N/A |
Some of the GM coaches had dual rear shocks on them which helps. We installed a rear stabilizer bar setup on our 4104, which almost eliminates all the side to side motion. Also the more pressure in tires and more air in airbags will help this, but at a harsher and higher ride height. Also tires with fewer plys will wallow more. | ||
| Bill Gerrie (Bill_gerrie)
Registered Member Username: Bill_gerrie Post Number: 155 Registered: 3-2006 Posted From: 209.50.74.6 Rating: N/A |
Bob Check your ride height in the front. If your leveling valve is letting your coach ride too high it will roll. Shocks play a big part in roll as well. Use Gabriel shocks instead of Delco. They are cheaper and stiffer so less roll. If you have a rear stabalizer bar make sure it isn't broken inside the rubber bushings where you can't see it. You might want to check your tire pressure as well. Less roll if inflated harder then softer. Just a few things to look for. Bill | ||
| Rob A (Otto)
Registered Member Username: Otto Post Number: 6 Registered: 12-2007 Posted From: 24.109.144.204 Rating: N/A |
Bob, I put up a sign... If this bus is a rockin Don't come knockin.. helped lots !!! Otto | ||
| Bob Baldwin (Bob4106)
Registered Member Username: Bob4106 Post Number: 152 Registered: 10-2004 Posted From: 24.74.180.20 Rating: N/A |
Thanks for all the help. After I change the air bags and shocks plus looking around for any other problems. I'll come back with a report |