Cold tires and cold roads and a rumbling ride

[OPCOM]

Drove the beast to work today, temp was 20-30 degrees. Aside from ice on the road it was OK, took a while to start. A 12x18" sheet of 1/16" neoprene on the grille helped the temp get up to 160-180 and stay there.

So, as the speed increased, there was more and more of a rumbling feel in the truck, to the point where I put it in neutral to verify it was not the engine and transmission about to go.. sure enough this remained. Nothing has changed since driving it in 50-60 degree weather. I have 60PSI in all the 11.00x20 tires.

Is this a normal thing coming maybe from the NDT tires, being very hard and cold? I doubt they ever did warm up. Not much of anything warmed up in fact. Has anyone else noticed this behavior or is something about to explode?

 

[dabtl]

Both of mine sit in the driveway, covered in ice even tonight. Texas is no place to practice driving a deuce in icy weather. Dallas was the worst possible choice for it.

I drove the SX4 Suzuki in all wheel drive for the entire day looking for the icy patches.

 

[randyscycle]

Here in VA it generally is in the 40's give or take for daytime highs in the winter and nighttime can go anywhere from 40's to zero.

I do notice that after the deuce sits for a week or two the tires tend to flat spot a little and in the colder weather certainly take a lot longer to get round again. Summer seems to not be an issue.

 

[dburt]

Bet it's flat spots on the tires- the older the tires, the more brittle and hard they are, and they take a flat spot set that is hard to work out, even more so in cold weather. I recently looked close at some of my rear tires on my M35, and found one that was manufactured in 1980. It shows 80% tread, but it is a hard, brittle tire. Thats why I put new radials on the front axle, makes me feel more secure about preventing a blowout on the highway at speed from an old hard brittle tire, plus in cold weather it makes for a much nicer ride, and easier to steer w/o power steering.

 

[Jake0147]

Sounds normal to me. Flat spots are worse when it's cold, and take longer to drive out of the tires when it's cold.

My driveway empties straight out onto a well traveled, 50mph truck route, so the engine is well warmed before I leave the driveway, but the tires are stone cold when they get to speed. If it's sat enough to get flat spots (which isn't long outside of the summer months) it's kind of interresting. There's a long, gentle curve as i head out, so the flat spots don't stay "in phase" with each other. First the flat spots line up, the cab jumps up and down pretty violently. Then it slowly smooths out. then a good shake and the wheel starts moving left to right. Slow, then more harshly, then it fades, then it smooths out. Then the cab starts hopping up and down again, gently at first, then more, then less... And after a couple or three or five miles (more in the cold) it straightens its self right out.

I love that curve... It's predictable. When somebody's riding shotgun you can wait just until the gentle "cycle" is done as you getting up to speed, then as it goes into the "smooth phase", just before you reach cruising speed, it's right ready to settle into the worst shake you're gonna get out of it... Just as you go by the old abandoned house... Look over and say "The only reason the army got rid of this so cheap was something about one of the front wheels kept coming loose, but it seems OK to me..."

 

[moparguy4x4]

the tires are bias ply that is why they flat spot so bad the radials wont do it unless sitting heavy loaded for a while i remember when i put the 40 inch hawgs on my truck for the first time and it sit all night on the black top in front of the old shop and the next morning i called dad and was like this thing is coming apart i think i broke a belt in the tire he said just drive it till the wheels fall off

 

[littlebob]

When I got my M51 from wreckerman and pulled it behind the Suburban in 40-50 degree weather it had been sitting for a little while at his place and probably a long place somewhere else. It took a couple hundred miles to get it up to speed. I started out feeling uncomfortable at 45, but was doing about? by the end of the trip.
littlebob

 

[Hammer]

When you have the tired fully aired up like that, they won't flex enough to warm up enough to get the flat spot out.
Try letting a bit of air out of the tires and try it again. 30 to 45 psi would be a good start.
Or, based on the weight, number of tires, and road conditions, just air them down until you see them just starting to sag a little.
The flexing of the tires with less pressure will warm them up a lot faster. And having less pressure is usually safer when it's cold anyways.

Warning though, letting the truck sit for longer periods of time with pretty low pressure and in cold weather will create some fairly obscene flat spots that will make your jaws hurt holding you teeth together

 

[Orionspath]

Month ago, picked up 2 more M35A2's in Pa. Snowed on the way up@ 0300hrs. @ 0830 I found myself wondering just when the heck the bumping would stop.

 

[uoa]

the tires are bias ply that is why they flat spot so bad the radials wont do it unless sitting heavy loaded for a while i remember when i put the 40 inch hawgs on my truck for the first time and it sit all night on the black top in front of the old shop and the next morning i called dad and was like this thing is coming apart i think i broke a belt in the tire he said just drive it till the wheels fall off

Punctuation is your friend! That is painful to read.

 

[cranetruck]

Patrick, you have radials in the front, right? The NDTs will take 5 miles or so to warm up under the conditions you are describing, based on my own experiences......

 

[Scrounger]

What you experienced is normal for bias ply tires. Most people are have used radials for so long they forgot about the cold spots that develop on bias ply tires when they sit. It usually takes 10 to 20 miles for the 11:00 x 20 NDT’s on my toys to smooth out for me. I just take it easy till they smooth out; beside it gives the truck time to warm up in the process.

 

[Pitbike94]

The deeper and wider the tread on the tire the more vibration and noise from them you will notice.

 

[undysworld]

Mine always vibrates too, unless she's loaded.

I'm not big on driving it in the cold though. Two years ago, I had to take a load into Madison, WI, on a cold January day. Mid-trip, the temp. dropped even further and started a freezing sleet. It was a real white knuckle ride. But the worst bit was the last turn into the driveway. When I barely tapped on the brake pedal, the tires locked up completely and I went nearly sideways towards the oak tree next to our driveway. I had the presence of mind to let the brakes off, at which time it rocketed straight ahead and safely up the driveway. I missed the oak by a foot, maybe.

Never again. In fact, this fall, we pulled the tree down with the truck. But my truck stays parked anytime it snows....

Be glad all you've got is a vibration!!

Cheers,
Paul

 

[undysworld]

Mine always vibrates too, unless she's loaded.

I'm not big on driving it in the cold though. Two years ago, I had to take a load into Madison, WI, on a cold January day. Mid-trip, the temp. dropped even further and started a freezing sleet. It was a real white knuckle ride. But the worst bit was the last turn into the driveway. When I barely tapped on the brake pedal, the tires locked up completely and I went nearly sideways towards the oak tree next to our driveway. I had the presence of mind to let the brakes off, at which time it rocketed straight ahead and safely up the driveway. I missed the oak by a foot, maybe.

Never again. In fact, this fall, we pulled the tree down with the truck. But my truck stays parked anytime it snows....

Be glad all you've got is a vibration!!

Cheers,
Paul

 

[OPCOM]

I do have "18 wheeler" radials in the front. The rears are all stock, and not too old, only about 4 years. Due to slow traffic, they may never have warmed up during the 22 mile trip each way. I was doing 10-30 most of the time.

There was not very much ice, mostly the bridges which I avoided. Anyway I am going to check all the lug nuts and the driveline etc. before I take it out again just for peace of mind. Oh - the only other difference was the lockouts were "in", but if that was the unlikely cause. then I have other issues.

Maybe it was the combination of flat spots and the NDT tread. When going slow, I could feel the bouncing motion that would always be there since two rear hubs are effectively locked together at all times.

 

[OPCOM]

Problem found. The cold weather was incidental to me noticing the symptom.

The bolts holding the front differential drive flange to the driveshaft flange were slightly loose. A 1/16" gap could be seen between one side of the flanges.

It pays to be attentive to every new vibration and noise. I realize I often post about strange feelings and noises and may blow them out of proportion somewhat, but there has always been a cause found later.

How this happened I do not know, but today I was pleased to inspect as many bolts as possible and lube the truck. I decided to check the grease gun before getting under the truck. and forgot to pull the handle back all the way. Only lost about an ounce. My pile of grease rags is increasing. Soon I will take them to the coin laundromat where one machine is labeled for "very dirty loads only - not for good clothes". I wish I had an old washer that could be used for this. I know better than to use my own washing machine.