Hook n ladder 1 Posted August 19, 2014 Share Posted August 19, 2014 Truck is 1998 CH613, E7-427/10sp Eaton, Eaton rear axles: The carrier bearing u-bolt let loose. I was able to pull over and stop before the drive shaft hit the street. It did get wedged up near the air dryer. New drive shafts, new carrier bearing, new u-joints from trans to first diff. The entire set up was put together and balanced before going on truck. They were put on truck with all u-joints "phased". So now I get a vibration on heavy acceleration, loaded, starting about 4th gear, and fades in about 6th gear (between about 1400-1800 rpm). Shakes the entire truck. Empty it's not as pronounced. If i'm loaded and real easy on the pedal, it too is not as pronounced. My mechanics not sure what it is. They thought air ride height was off but it's not. I was in need for new airbags. Four new airbags were installed. That didnt do anything for the vibration.Any ideas?Also, problem #2: I had the alignment checked earlier this year and it was in spec. However, my front left steer tire has worn down pretty quick....the outside of the tire is down to 2/32 while the outside is 7/32 ( with 36,000 miles on them) the other steer is 10/32 all the way across. I had the front end checked and everything is good. Any ideas on this? Maybe a re check on the alignment?I do mostly local semi-dump and some regional stepdeck stuff. Thanks Quote Link to comment Share on other sites More sharing options...
39 Baby Mack Posted August 19, 2014 Share Posted August 19, 2014 Had a similar problem years ago in an "F" model.Had the transmission checked and mainshaft was replaced, helped but didn't totally get rid of it.Finally ended up replacing the transmission.That took care of it.I don't know exactly what was wrong but I always thought the case was probably distorted.Ron Quote Link to comment Share on other sites More sharing options...
gearhead204 Posted August 20, 2014 Share Posted August 20, 2014 pop an axle out of each rear and run the truck up and look for problem ,your looking for run out on any yoke or vibration in any carrier brg. did a balance wt. get knocked off during installation ? did the shop recheck shaft balance after your complaint? as Ron stated maybe a bent shaft in the trans or power divider. running up the drive train with out the truck moving should help locate the problem.as tor the tires jack up each wheel ( one at a time) and spin the tire then use a jack stand as a steady rest and take flat screwdriver on edge and score a line on each tire then with the tires loaded (truck on the ground) take a tape measure and check toe in by measuring the distance from the line on the front face of each tire then the rear face of each tire you should have between 0-1/4 in. toe in (front face of tire) narrower than rear face. if this checks out you need a pro to fix the problem. Quote Link to comment Share on other sites More sharing options...
mrsmackpaul Posted August 20, 2014 Share Posted August 20, 2014 If there was no problem before the center bearing let go and there is now common sense would tell me there must be a problem with the new shaftas for the tyres you might have a crook spring hanger and one side is sought of lagging behind the otherPaul Quote Link to comment Share on other sites More sharing options...
jdfordhd Posted August 20, 2014 Share Posted August 20, 2014 Truck is 1998 CH613, E7-427/10sp Eaton, Eaton rear axles: The carrier bearing u-bolt let loose. .................Any idea? Would bet a stack of dollar bills you lost a spacer or shims when the carrier bearing dropped. Start stacking some washers between the carrier bearing and its' mount till the vibration goes away then fab a plate spacer this thickness for your permanent fix. OR. Go to Mack Parts to see if they show spacers for your truck. Could show a specific spacer. If the list shows shims "as needed", then you're back to experimenting with washers. Quote "If it ain't got a motor, I ain't interested.!!" Link to comment Share on other sites More sharing options...
Hook n ladder 1 Posted August 21, 2014 Author Share Posted August 21, 2014 Men thanks for your input. Back to the carrier bearing for a minute. Back in 2008 I had a reman motor installed. It vibrated like hell ( just like now). The dealership could not find the problem. An engineer came out from Mack, installed sensors all over the truck. It mostly pointed to the carrier bearing. So they changed it from a vented bearing to a solid rubber one. That helped quite a bit. This time, nobody seemed to know what I was talking about as only 1 type of carrier bearing is available. The shop I use and the dealerships had no idea of the 2 types. Looks like I have a vented one again. Is anyone familiar with this or was a smoking medicinal marijuana in 2008?I replaced the bad tire and have an appt for an alignment check tomorrow. Quote Link to comment Share on other sites More sharing options...
Hook n ladder 1 Posted August 27, 2014 Author Share Posted August 27, 2014 So I got an alignment, the steer and rear drive were off alittle so that should take care of the tire issue. I havent tried shimming the carrier bearing yet. The truck has not run right since replacing the carrier bearing.But some other funny things are happening. I have a 10sp Eaton. It feels a bit strange going into 5th and 10th...more so 10th. It goes into gear but doesn't seem to go all the way in. It doesn't jump out but just doesnt seem right.Also, my first drive axle is leaking oil from the side of the case (where the gasket/bolts are). Is this all coincidence or is it related to the carrier bearing failure? Quote Link to comment Share on other sites More sharing options...
mrsmackpaul Posted August 27, 2014 Share Posted August 27, 2014 If there was no problem before the center bearing let go and there is now common sense would tell me there must be a problem with the new shaftas for the tyres you might have a crook spring hanger and one side is sought of lagging behind the otherPaul As I said before Quote Link to comment Share on other sites More sharing options...
Hook n ladder 1 Posted August 27, 2014 Author Share Posted August 27, 2014 Paul i dont disagree with ya. Im going to run it by my mechanics and let them take a ride with me and theyll probably say the same thing. As far as a carrier bearing spacer.....the dealership parts guy there isnt one nor was my truck built with one. Quote Link to comment Share on other sites More sharing options...
gearhead204 Posted August 27, 2014 Share Posted August 27, 2014 have you put a dial indicator on the seal surface of the trans. yoke and rotated the yoke? you could have a bent shaft! same with the imput on the front diff. Quote Link to comment Share on other sites More sharing options...
Hook n ladder 1 Posted September 6, 2014 Author Share Posted September 6, 2014 All these things you guys have suggested have checked out. Even the new carrier bearing is at the correct angle.I've gone back into my records....so lets start overIn 2008 a Mack dealer installed a reman motor (427) After install it start to vibrate ( same as now). They sent a guy out from corporate with a computer and sensors. Best he came up with was changing the then "vented style" to a solid rubber style carrier bearing. Basically took care of the vibration but not 100%. In 2013 the front motor mount fell off, broke my fan and shroud. Everything else seemed ok but the truck seemed to vibrate a bit harder when engine idled (kind of like the old L10 cummins). So now here we are 2014 got a new vented carrier bearing ( thats all they make) and back to the vibration.Am i not looking in the right place? did something else happen when motor mount came out and engine fell down onto cross member?ThanksThanks Quote Link to comment Share on other sites More sharing options...
wheeler73 Posted September 6, 2014 Share Posted September 6, 2014 Possibly damaged the balancer. May not look damaged but it could be internally as they have a fluid in them. Just a thought. 1 Quote Link to comment Share on other sites More sharing options...
gearhead204 Posted September 6, 2014 Share Posted September 6, 2014 does the truck vibrate with out moving? or does the truck have to be in motion to act up? Quote Link to comment Share on other sites More sharing options...
Hook n ladder 1 Posted September 6, 2014 Author Share Posted September 6, 2014 In motion. It's worse loaded, mostly in 4th, 5th and 6th between 1500 and 1700 rpm. The bottom line is this started with the installation of a new engine. What ever is making it shake was masked by a solid rubber carrier bearing.Is the "new" flywheel and clutch out of balance? (They used the existing clutch). Quote Link to comment Share on other sites More sharing options...
mrsmackpaul Posted September 6, 2014 Share Posted September 6, 2014 to me the only simple option is if you had another truck the same you could swap the drive shaft with another truck if the problem shifts the problem is in the drive shaft aside from that maybe a balancer issue maybe the input shaft to the gearbox was damaged or the bearing in the front of the box ? I started typing the needle rollers between the input and out put shafts in the box but then I had a thought !!!!!!!!! they arent spinning when youre in top gear well at least they arent in a Mack box but the input and output shafts are only carried on the bearings at each end when your in top gear so maybe the the those needle bearings between the two shafts help to cancel out the vibration but it cant when your in top gear because they are not spinning as in the shaft is coupled together I dont no if this makes any sense anyway disregard if Im waffling to muchPaul Quote Link to comment Share on other sites More sharing options...
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