"Willy Mammoth" - Volvo 730 RV Hauler Build

[Alie&Jim's Carrilite]

Are you sure the vibration is in the suspension? A driveshaft that is slightly out of balance can drift in and out of vibration depending on rpm's, load, etc.

[bmzero]

Are you sure the vibration is in the suspension? A driveshaft that is slightly out of balance can drift in and out of vibration depending on rpm's, load, etc.

Well, I guess I can't be sure, but the vibration existed before singling axles. When I singled, we replaced all u-joints, hanger bearing, and balanced the newly lengthened driveshaft. All of that, including removing a rear axle, had no affect on the vibration. The most benefit was realized from replacing the front shocks.

[Alie&Jim's Carrilite]

Ok, I can suggest several things that might or might not work, like swapping the front tires side to side and see if it's better or worse, or having a set of centramatic wheel balancing rings installed. Someone recently commented to me that if the vibration was in the steering wheel it's the front end. If the vibration is in the seat, dash, cab, etc. then the issue is in the tires. And their truck drove and rode as smooth as silk.

[HERO Maker]

Have you tried truing your tires? You said you were balancing / spinning the tires? If you are able to get the tires off the ground and get them spinning fast, you should be able to set something against the tread and see if they wobble at all. None of these tires come from the factory without a bit of a bounce. Balancing them can take away some of the out of balance weight of the tire/rim, but truing them will cut off the little bit of imperfection of the tire being out around. I've seen brand new tires go on companies trucks, and the first thing they had done to the tires was truing. You might be able to research it in the resource guide, like right here, or search for an older thread.

[ATCBoomer]

Have you had the tires pulled off the rims to see if possibly they used a liquid balancing substance. I had a vibration just like this on my truck but I could see the worn spots on the right front tire. I replaced the tire and let the guys at the shop talk me into putting a liquid that supposedly balanced and sealed the tire if I got a puncture. I left expecting a great ride, nope it was way worse. When I replaced the left front tire I had them pull the right one off and remove the liquid. It looked like a white mud in the tire. Tire place had never seen anything like it. Cleaned it all out, put balancing beads in it and that did the trick. Might be worth looking into. May just need a new set of tires.

[bmzero]

I have swapped the front tires from side to side. It made no difference.

 

Alignment pins and balancers are still an option. However, this truck has "balanced" drums and the tires balance well.

 

When off the ground, the tire that is currently on the driver's side shakes a little, but I don't think it's enough to cause this issue. Out of round could still be an option, but spinning doesn't reveal major issues there.

 

I'm of the same opinion, though. It still feels like tires to me, even though it has been in four tire shops. I guess if I want to pursue tires as the culprit, I need to purchase a new set of steers or find someone who would temporarily swap fronts with me.

[bmzero]

Have you had the tires pulled off the rims to see if possibly they used a liquid balancing substance. I had a vibration just like this on my truck but I could see the worn spots on the right front tire. I replaced the tire and let the guys at the shop talk me into putting a liquid that supposedly balanced and sealed the tire if I got a puncture. I left expecting a great ride, nope it was way worse. When I replaced the left front tire I had them pull the right one off and remove the liquid. It looked like a white mud in the tire. Tire place had never seen anything like it. Cleaned it all out, put balancing beads in it and that did the trick. Might be worth looking into. May just need a new set of tires.

That's definitely a possibility, but I think I would feel that when we spin the tires on the truck.

 

Unfortunately, the tread on these tires is almost brand new. If they were worn, buying steers would have been my first attack.

[Jack Mayer]

I was going to say what Rocky did - check the tires for true.....that will cause the EXACT symptoms you are describing. And, BTW, do not assume NEW tires are true. I have seen some new ones that were WAY out.

[DamianF]

Have you checked your spindle bearings (front hubs) for wear? The shake of the left tire off the ground that you mentioned might still be the symptom of the root cause of your vibration. The only other things that flashed through my old brain cells are worn motor mounts or a failing ancillary component on the front of the engine that could cause a vibration that seems like front end but isn't.

[bmzero]

Have you checked your spindle bearings (front hubs) for wear? The shake of the left tire off the ground that you mentioned might still be the symptom of the root cause of your vibration. The only other things that flashed through my old brain cells are worn motor mounts or a failing ancillary component on the front of the engine that could cause a vibration that seems like front end but isn't.

 

The passenger side kingpin is a little loose, but not enough to be concerned with. I don't think that is the cause. I have checked everything for play, as much as myself and two other mechanics know how to check.

 

I have considered the motor mounts being the culprit. I think that's a real possibility. I'm going to check those as I can get some time.

[Broncohauler]

We have this problem all the time with our company Penske leased trucks.

Try the best you can to narrow it down as to what and where you feel it.

For us it's The front end alignment but Penske won't do alignments they just replace steer tires every time we get the shakes.

 

You said 40-45 mph Try The best you can to narrow it down. Are you feeling the vibration in the steering wheel look at the steering wheel when it's occurring it might be shaking very slightly. Play with your speed to make it more pronounced. If so it's in the front end. Replacing the tires only hides the problem for in my case maybe 25k miles.

Do you feel The vibration in your feet or the seat-of-the-pants but not in your hands?

If so then it's driveline. But if the problem was there before singling and is still there after I more likely to think its your front end.

[Broncohauler]

Also The last time I had the shakes and they swapped my tires. They moved the front tires to a rear axle. And put new tires on my steers. The tires they took off my steers and put on that rear axle to run out still gave me the bad vibration but now in the rear.

[noteven]

bmzero does the vibration sort of continue through a corner while maintaining the same speed i.e. when the steering force "takes the slack" out of anything out of tolerance in the steering system or king pins?

 

I expect the tire shop checked the tires for mismount where the bead is not fully seated - which causes a vertical out of round condition.

[Bob Cochran]

Okay am going to throw this out there but would think all those tire shops and yourself would have found this. Around the bead of the tire is a raised ring or line in the tire. Its purpose for those that don't know is to make sure the tire is mounted equidistant or centered on the wheel. In other words that ring should be the same distance from the wheel edge all around, if not the tire is not centered on the wheel. I am not sure I explained this very well but I do know the quality of people that mount tires is lacking and have seen this happen more than once over the years.

[bmzero]

Bob and Noteven, I believe you guys are describing the same condition. I have lifted the front of the truck up in the air and put one of those fancy high-speed spinning machines on either side, one side at a time and spun them up to speed, all along the way checking for smoothness of the tire rotation. I believe this would have shown the problem you're describing. However, I will definitely look at it again in the morning.

 

Yes, the vibration continues through a corner, no matter what I do. That was one my first seat-of-the-pants tests. While vibrating, nothing I did seemed to affect it (letting off the accelerator pedal, pushing the brakes, cornering, etc.).

 

What's even more odd is it seems to come and go. I drove the truck, attached to the trailer, for about 2 hours this evening. There were times where I barely felt the vibration, but others where it was a lot more pronounced.

 

I have four possibilities still on my list, in order of what I think is more likely:

1. Bad tire
2. Front ride height level (for sure the passenger side front bag is leaking slightly)
3. Engine mount (less likely due to releasing the accelerator pedal not having an affect on vibration)
4. Out of balance. I think the tires are good, but when combined with the drums, maybe there's a problem. It had centrifugal ring balancers on it when I got it, but they had solidified, so I removed them. Maybe I should try a new set.

Another thing that I'm slightly concerned about is the amount of slack in the output shaft of the transmission. While under the truck, I can move the driveshaft up and down about a 1/4". I asked the Volvo tech to check that and adjust if necessary. He said everything looked good to him. I just sort of nodded my head. Seems strange to have that much play in the output shaft. I can't say that it would cause this issue, but it does seem possible.

[DamianF]

That drive shaft or yoke play could be the problem.

[Bob Cochran]

Yes me and Noteven are probably talking about the same thing. I would think spinning it as you did it would be obvious. You have on your list bad tire and I thought of that but didn't you say you moved tire between sides and still had vibration it did not move with the tire? If you did not a bad tire i would not think. The mystery continues!!!! I bet you will find it though.

[peety3]

Draw whatever conclusions you wish from this: back in 2002, I replaced the Firestone tires (load range D, so 8-ply) with Michelin LTX M/S tires (load range E, so 10-ply) on my Ford Excursion. Everyone told me they'd be rougher because of the extra two plies. They were wrong: Michelin makes a fine product, and they were oh-so-smooth. A week later, I took the truck to a well-respected tire shop that services everything from little Mazdas to fire trucks and big rigs. They did truing, balance, and alignment on the tires, but I came out thinking they'd secretly replaced my Excursion with a Folger's Cadillac: it rode smoother than a baby's bottom, tracked straight as an arrow for miles, and stayed that way for a long, long, long time. IMHO, even if it doesn't fix your vibration problem, it'd be money very well spent. Southwest Brake & Alignment, San Antonio TX, off I-35 near the Splashtown water park and BAMC (or SAMMC as they call it now I think).

[noteven]

^{bmzero I think you are saying the vibration or shake is more of a wheel speed condition (lower rpm) vs driveline / engine related rpm?}

 

^{Is it constant?}

 

^{Is it present when you are bob tail & hauling your trailer, no difference?}

[bmzero]

Draw whatever conclusions you wish from this: back in 2002, I replaced the Firestone tires (load range D, so 8-ply) with Michelin LTX M/S tires (load range E, so 10-ply) on my Ford Excursion. Everyone told me they'd be rougher because of the extra two plies. They were wrong: Michelin makes a fine product, and they were oh-so-smooth. A week later, I took the truck to a well-respected tire shop that services everything from little Mazdas to fire trucks and big rigs. They did truing, balance, and alignment on the tires, but I came out thinking they'd secretly replaced my Excursion with a Folger's Cadillac: it rode smoother than a baby's bottom, tracked straight as an arrow for miles, and stayed that way for a long, long, long time. IMHO, even if it doesn't fix your vibration problem, it'd be money very well spent. Southwest Brake & Alignment, San Antonio TX, off I-35 near the Splashtown water park and BAMC (or SAMMC as they call it now I think).

 

Peety, I think that's good advice. I just wish it wasn't attached to a $1500 bill. I would really like to do that, but I have quite a few other places that need $1500 more than the tires. It may come down to the tires being the culprit, but they will probably be swapped out last. I'm doing all of the things that need repair anyway.

 

What steer tires does everyone recommend for these trucks? If I could find a tire that would yield a better ride (over small choppy bumps), I could more easily justify the expense as an "upgrade" rather than gambling that it would fix my vibration.

 

The next item on the parts replacement list is the front height control valve. It is definitely leaking and seems to be the culprit of front end vibrations for others on the air spring trucks (http://www.thetruckersreport.com/truckingindustryforum/volvo-forum/144350-air-ride-height-post1951610.html#post1951610). Since the valve needs to be replaced anyway, it's the obvious next thing to do. It seems like a stretch to me that it fixes the issue, but even after a front and rear alignment, it still pulls to the right pretty good. In this case I hope 1 + 1 = vibration.

 

 

^{bmzero I think you are saying the vibration or shake is more of a wheel speed condition (lower rpm) vs driveline / engine related rpm?}

 

^{Is it constant?}

 

^{Is it present when you are bob tail & hauling your trailer, no difference?}

 

I don't feel that it's engine-rpm related because I don't feel it in any other gears. It feels more speed-related, but I'm not ruling out the driveline simply for the fact that I had to take the driveshaft back to the driveline shop to have them lengthen it AFTER they came out and measured for it the first time. That took away the confidence I had in them doing the job correctly the first time. However, the vibration is the same as it was when I bought the truck (with both drive axles).

 

Pulling the 5er seems to make no difference.

 

Another possibility, mentioned earlier, is bad engine mounts. When I turn the engine off, it seems to rattle and "clank" more so that I expected. Not being around any other trucks, I don't know if that's normal. Do you guys get a lot of noise like that when turning off your engines?

[peety3]

 

Peety, I think that's good advice. I just wish it wasn't attached to a $1500 bill. I would really like to do that, but I have quite a few other places that need $1500 more than the tires. It may come down to the tires being the culprit, but they will probably be swapped out last. I'm doing all of the things that need repair anyway.

Ouch! Have you shopped that price around at all? I know it's by no means an apples-apples comparison, but I was able to get two Excursions (don't ask...) trued/balanced/aligned (with some shims added to the bill) for <$325 total.

[bmzero]

Ouch! Have you shopped that price around at all? I know it's by no means an apples-apples comparison, but I was able to get two Excursions (don't ask...) trued/balanced/aligned (with some shims added to the bill) for <$325 total.

 

No, I have not. I just grabbed a popular Michelin tire and did a quick Google search on it - https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&es_th=1&ie=UTF-8#q=Michelin+XZA3&tbm=shop. I'm sure there are better prices out there, but either way, by the time I add tax/mount/balance/truing to them, they'll easily be over $1000 for a set of high end Michelins.

[HERO Maker]

bmzero,

 

I think the point the peety3 is making is:

"A week later, I took the truck to a well-respected tire shop that services everything from little Mazdas to fire trucks and big rigs. They did truing, balance, and alignment on the tires, but I came out thinking they'd secretly replaced my Excursion with a Folger's Cadillac: it rode smoother than a baby's bottom, tracked straight as an arrow for miles, and stayed that way for a long, long, long time. IMHO, even if it doesn't fix your vibration problem, it'd be money very well spent. Southwest Brake & Alignment, San Antonio TX, off I-35 near the Splashtown water park and BAMC (or SAMMC as they call it now I think)."

 

As has been mentioned, and from personal experience, I can tell you that when they put the white paint (or whatever) on the tread of your tire, and then start shaving it off with their blades while your tire is being spun around, you are able to see all the "high" black tire areas that are coming off first, with many "untouched" white areas until the job is complete. The total price for this should be close to what he quoted.

 

Even on new tires! (which I think was the point).

[bmzero]

bmzero,

 

I think the point the peety3 is making is:

"A week later, I took the truck to a well-respected tire shop that services everything from little Mazdas to fire trucks and big rigs. They did truing, balance, and alignment on the tires, but I came out thinking they'd secretly replaced my Excursion with a Folger's Cadillac: it rode smoother than a baby's bottom, tracked straight as an arrow for miles, and stayed that way for a long, long, long time. IMHO, even if it doesn't fix your vibration problem, it'd be money very well spent. Southwest Brake & Alignment, San Antonio TX, off I-35 near the Splashtown water park and BAMC (or SAMMC as they call it now I think)."

 

As has been mentioned, and from personal experience, I can tell you that when they put the white paint (or whatever) on the tread of your tire, and then start shaving it off with their blades while your tire is being spun around, you are able to see all the "high" black tire areas that are coming off first, with many "untouched" white areas until the job is complete. The total price for this should be close to what he quoted.

 

Even on new tires! (which I think was the point).

 

Understood. However, I not sure I want to throw another $300+ at these tires. I would rather spend that money on a new set of tires and have them trued. At this point, it's a gamble either way, I guess. If I knew $300 would fix the vibration, easy decision, but that's not the case here.

[ATCBoomer]

Take those tires and spend the 25 dollars per tire and have them pull them off the rim and make sure there is no fluid of sorts in them before you go out and but new tires. Speaking of buying new tires, consider this, do you really need to spend the money on high dollar tires that you will replace due to dry rot instead of wear. I bought a samson steer tires for $350 installed. I know, I know, these are Chinese tires but only a handful of tires aren't made in China these days. I put the balancing beds inside my tires when I had them changed. Just a thought.