• Steel Soldiers now has a few new forums, read more about it at: New Munitions Forums!

  • Microsoft MSN, Live, Hotmail, Outlook email users may not be receiving emails. We are working to resolve this issue. Please add support@steelsoldiers.com to your trusted contacts.

M939A2 / M923A2 bucking/bouncing at 25 to 35 mph

Alexsha

New member
318
3
0
Location
Cache Valley, UT
Under 25 and over 35 mph my truck is pretty smooth. At 25 to 35 I get some severe bouncing/bucking. This is on flat roads. Would this be a wheel balancing issue? Wheels out of round? Shocks/springs? I know these trucks are not smooth rides, but the bouncing is pretty intense.
 

73m819

Rock = older than dirt , GA. MAFIA , Dirty
Steel Soldiers Supporter
In Memorial
12,195
319
0
Location
gainesville, ga.
What is the air pressure in the front tires, is the front axle OUT of front wheel drive (never mind if the light is on or not) that you know for sure ???
 

MuleMac01

Military vehicle collector
Steel Soldiers Supporter
890
158
43
Location
Las Vegas Nevada
Make sure your truck has the C.t.I.s counter weights on the front tires and that there opposite of the c.t.I.s valve on the tire.
 

Alexsha

New member
318
3
0
Location
Cache Valley, UT
What is the air pressure in the front tires, is the front axle OUT of front wheel drive (never mind if the light is on or not) that you know for sure ???
55 psi in front passenger. 62~63 psi in front driver.

Later today I'll take it out and engage/disengate the front axle, but I'm fairly sure it's not engaged.

Make sure your truck has the C.t.I.s counter weights on the front tires and that there opposite of the c.t.I.s valve on the tire.
Yes, CTIS counter weights are present and opposite the valve.
 

Jason O

Member
107
2
18
Location
Lebanon PA
You likely have one or more tires out of round. My truck felt like it had Fred Flinstone tires until I had them buffed/ shaved to bring them in true. I lost a good bit of tread in the process but it was worth it.
 

VPed

Well-known member
Steel Soldiers Supporter
1,104
294
83
Location
Clint, TX
O.K. then, I'll try to be more helpful. Both my deuce (on 395s) and my 5 ton have bouncing issues at certain speeds that I can affect with tire pressure. Airing down usually will work to reduce my vibration below 40 mph. But I have to air down quite a bit so I limit this to when I will not be going faster. If I have highway time in my plans, I go with higher pressures and avoid the vibration speeds.

I do not have CTIS but I did read a thread that indicated that the counterweights are actually a little too heavy to properly balance against the CTIS valve. Maybe you can pull a front hub cap and jack up that tire. This might show you which is the heavy side and that can guide your remedial actions.
 

71m109a3

Member
92
3
8
Location
PA
I have the same issue around 40 mph with my 109. I have 11.00 XL's all around. Front axle not engaged. Run 60 lbs. front and 50 rear.
My 109 does too. I have 9.0 NDCCs and have swapped them around and replaced a few to no avail.
 

joesco

Member
442
1
18
Location
Hampstead, NH
My Super Singles, Michelin 14-20's do the same thing. Brought it to the local truck tire shop and they suggested re-groving them for $150.00 per tire, which would bring them back to new.

My guess is that the more I drive him, the uneven wearing will "may ", as the BBTB (Big Boy Toy Budget) is depleted!
 

MuleMac01

Military vehicle collector
Steel Soldiers Supporter
890
158
43
Location
Las Vegas Nevada
Rotate the tires if that doesn't help balancing beads, and put about 1,000 pounds in the back should smooth it out nice. Most of the trucks have had the same tires for years and sat on them for years... out of rounds tires is a big problem. Mine does it at 55-60Mph but smooth as glass below.
 

QUADJEEPER

Member
Steel Soldiers Supporter
797
6
18
Location
Winter Springs, FL
During my brake and wheel bearing service, I spun the tires with the axles out and didn't see any major out of round tires. Too much bearing drag to check for balance issues. I have tubes, so not keen on putting anything in the tires for balance. Anybody have any experience with Centramatic balance plates? They mount to the lug pattern behind the wheels.



You likely have one or more tires out of round. My truck felt like it had Fred Flinstone tires until I had them buffed/ shaved to bring them in true. I lost a good bit of tread in the process but it was worth it.
 

Tinstar

Super Moderator
Super Moderator
Steel Soldiers Supporter
4,284
1,766
113
Location
Edmond, Oklahoma
Mine does that also if I haven't driven it for a while.
Slow speed and short trip will not smooth out the flat spots.
A nice trip that allows the tires to heat up and higher speeds always works for me.

Remember all of that truck weight on that one tire spot over time will not make it happy.
 

QUADJEEPER

Member
Steel Soldiers Supporter
797
6
18
Location
Winter Springs, FL
Thanks Lindsey97, I think my bounce is from the rear, so I may try a full set if they have them in the correct bolt pattern and when (if) I can save up for them. As for the flat spotting Tinstar, I have driven over 90 miles in one run without smoothing out. And no terra firma attached either Bchauvette. Someone told me that all 109's did that. I'm not convinced. Yet.


quadjeeper-- I have centramatics on one of my dump trucks and I think they work wonders on my steer axle. do not have them on my m923a1.
 
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website like our supporting vendors. Their ads help keep Steel Soldiers going. Please consider disabling your ad blockers for the site. Thanks!

I've Disabled AdBlock
No Thanks