| Author |
Message |
Jerry Wilson
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, October 19, 2005 - 11:23 pm: | |
Hi All, what would be the main cause of excessive side sway when changing lanes.It happens usually at 70 to75 mph.I slow down a bit and it will stop.Its like being in a boat. The bus drives great except for the swaying |
John MC9
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, October 19, 2005 - 11:36 pm: | |
Yikes?
Not meaning to be insulting, but not knowing anyone's experience
driving one of these boats, please allow me?
"excessive side sway when changing lanes.It happens usually
at 70 to75 mph."
A 40' box (esp with two axles) should be treated with kindness.
I had been taught to change lanes 1/3 area at a time. Pull
into 1/3 of the lane, and then another 1/3, and then the last 1/3,
and give a moment to check mirrors with each gentle move.
That gives a motorist time to get out of your blind spot (if he's
in it), and time for you to make sure you're not running some
motorist off the road. But it also provides a smoother ride.
There shouldn't be any sway if the move is made as slowly,
and as gently as it should be made. |
Marc Bourget
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, October 20, 2005 - 1:36 am: | |
Not enough info. Is the body swaying or is the bus exhibiting hesitation in changing lanes. Are your tire pressures correct, or are your axle locating bushings properly maintained.
Lots of variables that need to be eliminated in an orderly and intelligent fasion |
H3-40
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, October 20, 2005 - 8:26 am: | |
Our 4107 was notorious for swaying. It had excessive steering wheel play which meant it needed a new steering box badly. The adjustment was not to be found as in, it was all used up. You may want to have it checked on yours as well!
Ace |
Jerry Wilson
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, October 20, 2005 - 7:25 pm: | |
As i said, the bus drives ok. The steering seems ok. If you hit a hard dip that starts a side motion it continues till i slow down or if i turn the bus slightly as in a shallow turn .It will stop swaying on its own but is unsettling.Because of the swaying i am very carefull in changing lanes.I am an experienced" school"bus driver and have checked tire preasure, my thinking was bad shocks or reaction from bad leveling valves Thanks Jerry 4107-071 |
David Hartley (Drdave)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, October 20, 2005 - 8:04 pm: | |
horizontal sway bar bushings and bad shocks may be the problem.
Leaning on the steering in either direction from center causes the sway bars to engage probably due to worn out bushings. It's as loose as a goose under there....?????
You need to put the bus over a pit with the suspension aired up and check the bushings, Just jacking it up may not work. |
john w. roan (Chessie4905)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, October 20, 2005 - 9:16 pm: | |
If the shocks are old, consider replacing them. Nice thingis,they are suprisingly cheap, because they fit a lot of different coaches.Check to see if it has both front and rear sway bars. If it doesn't have a rear one, get one. Also make sure you don't have a broken rear stabilizer bar to body connecting link.Other suggestions above are right on also.There can be other causes also, but these are a good place to start |
Jerry Wilson
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, October 20, 2005 - 9:27 pm: | |
I will check the steering gear ajustment ,but it seems ok. David, the horizontal bar you are refering to is on the front ? According to the manual The 4107 has one ,on the front ,none on the back . I know the stabilizer bar links were replaced before we got the bus, almost a year ago. Appreciate the help Jerry |
Phil Dumpster2
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, October 21, 2005 - 2:56 am: | |
Check the floor near the rear of the coach - it's a structural member in that coach and if the fasteners have pulled through rotted plywood, or if the fasteners have failed, it will cause the kind of swaying you are experiencing. |
FAST FRED
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, October 21, 2005 - 5:39 am: | |
The stering gear is very slow to wear and overtignting it will only cause it to go South that much faster.
Most GM I have seen only need the splined coupling with 2 universals renewed.
A fast, cheap (under $100) job that should only take a half hour and may remove a half turn of slop.Grease the new splines annualy.
Call LUKE at US Coach , 1-888-COACH 34 , he is having them made again.
Worked for me,
FAST FRED |
John MC9
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, October 21, 2005 - 8:31 am: | |
Uhm.
It's funny how a simple question will result in complex thinking.
The question was:
"what would be the main cause of excessive side sway when changing lanes.
It happens usually at 70 to75 mph. I slow down a bit and it will stop."
Not when changing lanes at 50-60 mph; only when changing
lanes at 70-75 mph?
An '07 never was a sports car. Tire pressure, etc., all matters, but
too quick a move while travelling at that high speed, with that much
weight on two axles, and that thing is going to do some leaning and swaying. |
Jim Bob
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, October 21, 2005 - 2:20 pm: | |
Can you say what you are comparing the amount of sway to? An air suspension GM bus will sway (and/or lean) WAY more than a regular school bus, which pretty much has a truck suspension. It is scary at first (and a little at times later). We have a 4104 which is not as tall as your 4107 but has no stabilizers at all. It leans WAY over in turns even at slow speeds. I have learned to follow a procedure like John describes.
If you mean that the bus sets up an oscillation from side to side when you change lanes like a trailer without enough tongue weight then that's a different and dangerous matter.
How much play is there in the steering when you are rolling along at about 5 MPH? |
RichInternational Bus & Parts
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, October 21, 2005 - 2:23 pm: | |
Jerry,
I agree with Dr Dave. Start with the obvious. Sway bar bushings........The name says it all. Radius rod bushings & shocks can come into play as well. The new polyurethane bushings will firm up the ride & give you better handling.
If the coach is overloaded to one side or the other, the "unbalance" can also contribute to excessive sway when moving from left to right.
Thanks
Rich
800-468-5287 |
Jim Bob
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, October 21, 2005 - 2:27 pm: | |
Tire pressures can be part of this too. Soft tire/s on one corner can cause bad swaying. |
Jim Bob
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, October 21, 2005 - 2:31 pm: | |
Tire pressures can be part of this too. Soft tire/s on one corner can cause bad swaying. |
john w. roan (Chessie4905)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, October 21, 2005 - 7:42 pm: | |
If you don't have a rear stabilizer bar GET ONE! ( after you get this rocking fixed) . Put one on our 4104... what a difference!!! and a 4107 is taller. One really bad shock could set up the ocillations also.If you don't do much of your own chassis work... get someone like Luke to check it out for you. Should have a pit and someone with proper knowledge check it out. Depending on where you live as you don't have any info on your wherabouts; someone on this board can give you a good recommendation. |
Jerry Wilson
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, October 21, 2005 - 11:35 pm: | |
Thanks for all the input everyone. I will be looking very close at the bushings on the stabilizer bars front and rear.I have no idea what kind of condition the shocks are in but they can't be to good.I am going to do some extensive work on the front end"air bags "and will check out all that i can. Thanks again, Jerry |
FAST FRED
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, October 22, 2005 - 5:26 am: | |
GO for a 20 mile ride and CAREFULLY touch each shock.
They will be warm if working , cool if shot.
I would start with shocks first , and find a pit to look for shot bushings if that doesn't work.
Beware of the Polly bushings , many folks think they transmit far too much noise and harshness for miniscule results.
Some GM's are indeed be The Sportscar of Coaches ,
but parts suitable for a racing Porsche may not be great fun on a camper.
FAST FRED |
johnwood
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, October 22, 2005 - 7:40 pm: | |
FF;
Excellent tip on the shocks!!!
Makes all the sense in the world.
Thanx. |