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Took the truck to registration check the other day. 30 minutes drive one way.
It passed swedish registration by the way !!

But I had some vibrations in higher speed.

When I got it home from US last winter I realized they had moved the truck around on the ship from US with a big forklift and one driveshaft was seriously bent. I have left it to be straightened out and it is checked and balanced. Still vibrations.

CAn it be the bearings ?

http://www.classicparts.com/1954-98-Drive-Shaft-Support-Bearing-T1/productinfo/92-905/

This website says up to 1 ton.

Does the 2 ton have another driveshaft ?

Fits 58 to 94 1/2 ton, 54 to 94 3/4 ton, 56 to 98 1ton, 1.3780" bore.

There are about 3 different sizes of driveshaft center bearings, and there's a good possibility yours will be the next size larger than the one in the link. Fortunately, they're not usually brand-specific. The same bearing might be found on Ford, Dodge, International, Chevy, etc. Another thing to check for is the phasing of the driveshafts. If the front and rear shafts are assembled with the splines a tooth out of phase, the shafts will vibrate even if each one is perfectly balanced individually. The U-joints should be made to flex exactly 90 degrees apart by making sure the splines of the slip yoke and the mating shaft are aligned properly. Not all shafts and slip yokes have keyed splines that cannot be assembled incorrectly.
Jerry

Hotrod is right. I found out the hard way on ald Chevy school bus that I put u-joints and bearings in. I didn't get the shafts phased right and there was a vibration. When I found out what I had done I felt kind dumb. On this bus it was long enough it had three shafts. One off the transmission, one in the middle of the coach, then the last one connected to the rear axle.

I had one just a couple of splines off from the rest.

Hmm... that is probably the the reason.
Because I had just the middle one off the truck, and when I put it back in it was not that easy, but by looking it seemed straight. I did put it exactly as the shopmanual said.

But one or two might be wrong, will measure it later today with a straight long ruler as a guide.

I knew it when it was removed already that I should have made a big marker somewhere as help when it was time to remount.

I'll just have to redo it

I'm interested- - - -how was the driveshaft "straightened"? In about 50 years of working on them, I don't think I've ever seen a bent driveshaft straightened successfully. It's always necessary to replace the tube and check the assembly for runout in a lathe during the rewelding process on the ends. Then the re-tubed shaft is spun in a balancing machine and weight is added like balancing a wheel to take out any remaining vibration. The most common balance weight is a small flat washer, tack-welded to the tube near one of the yokes. The maximum runout most driveline shops will accept is about .015 inches.
Jerry

I agree that the only way to straighten a drive shaft is to replace the tube. If you can't get the size tube on Sweden, either have a complete shaft built to accommodate the U-joints or have a tube cut from USA. I have watched shafts being built in Germany, but I never inquired if the tube was inch or metric.

The shafts of the 70's era MB trucks were metric. I changed the wheelbase on a lot of them to better accomodate van bodies and had to cut the drivelines. The u joint parts were a european product and we came up with a Spicer driveshaft that worked.

Incidently on Jerry's comment about runout we held ours to .005 at the weld yokes nad midship stubs and never had a driveshaft come back for any reason. I did not have a balancing machine and know for a fact that it is a production shortcut as getting them to a very close tolerance we held is time consuming but it works.

I too have never heard of anyone successfully straightening a driveshaft. They must be retubed or replaced. A tube & yoke [censored]'y will save you money over just replacing the tube.

I made a wrong and incomplete statement.
I got it straightened. By cutting the tube, remove the bent part, and add a new tube.

So infact they did NOT straighten the bent tube.
I got a straight one back thou

I have to get better at expressing myself.

Tomorrow I will check if I mounted it correct

I have corrected it now, it was 2 splines wrong.
But it will not line up 100% so I realize that when they cut the tube and put in a new tube, the relation between other end and splines were not considered.

So how ever I do now I get it HALF of a plien to the left or right from center.

HAven't tested it on the road yet, but can HALF of a spline do a big differance. Saw in the shop manual that a 5100 shall have it adjusted ONE SPLINE clockwise. All other models shall have a straight lineup...

If this is not good enough I will just have to remove the middle tube AGAIN and weld it back 2 mm to the right or left....

Puh....

Vibration is gone when accelerating, and when I go on steady speed.
When I let go of the gas pedal and engine break only I still have some vibrations, so I still think I need to replace the center bearings before next summer, but at least now I can drive it and my hat is still on when I get out !!!

Take it to someone who knows what their doing and have it properly repaired. They will need the slip yoke or midship yoke or another matching shaft to mate/phase it to. I don't know what you have on this truck but I understand exactly what your problem is. It isn't likely that a driveline repair shop in Sweden will have the attaching parts and thats why I suggest taking enough of what you have and they will need to correctly fix it.

We have shops here that build completely new ones, like original, both for trucks and cars. For racing and for normal driving.

But they have no competition in Sweden, all alone. So they can charge whatever. So that's what they do !!

That's why we have to give it to someone who "almost" is as good... and maybe know what they are doing.

It's balanced alright.

But I know, if you do it correct you should take out all three of them together, and have them balanced as one unit.

But here.. nope would cost a fortune.

I have repeatdly stated that balancing is not required.
1. is a production shortcut
2. cheaper than the time consuming tolerances or .005 at the ends and hold to .012 in the tube middle &phased correctly
3. not enough rpm's to be of a concern anyway if done correctly.

4. almost is what you have now and it's wrong. Go figure.

Yes, the 1/2 spline misalignment will cause a small vibration, but probably not enough to cause premature wear of the U-joints. It will only be a driver comfort concern. If you can live with a slightly imperfect arrangement, go for it. If the shop that re-tubed the shaft is willing to correct their mistake, take the mating slip yoke that fits the misaligned spline with you so they can index it properly as it's rewelded.
Jerry

LOL Glad to see all the guys got you and your drive shaft straightened out

I get your point
Finally... I am a bit slow sometimes