My 55 "C" 600 CAB OVER ENGINE-or CAB FORWARD "Tool" truck has developed a growl and a roughness/vibration that I am chasing down. I can feel the roughness/vibration with the rear tires off the ground. While on jack stands I ran the truck but found the growl to be greatly reduced and a curious thing. I did find the rear section of drive shaft that attaches to the pinion coupler bouncing/hopping where the other sections dont do that at all. So I will take that section of the shaft to get it balanced tomorrow. All 6 of the u joints and both of the center support bearings were replaced when the box was installed in December 2015 Ive only put about 10,000 miles on the truck in that time. They seem fine except for the rear most center support bearing even though low on miles and time has some growl to it which has me wondering about it. I will re check it after I reinstall the freshly balanced drive shaft. The pinion seal for this EATON-FULLER 1350 rear Axle.has leaked the whole time Ive had this truck. I removed the pinion seal and its bearing yesterday and am waiting for Green Sales to send me a new Pinion Seal housing/seal flange assembly. Usually I have parts waiting to do the work...this time without explanation I didnt and now have to wait....
I need the brain trust here to weigh in...The Pinion bearing cone surface area where the spacer washer makes contact---in other words the back area where the "TIMKIN" and its Part Number are stamped has some deepish scratch marks and some pitting---there is rust present there....but the rest of the bearing--rollers/cage etc looks clean nice....Are those marks an issue?

Note the scratch/pitting next to the "Timkin" and all along that flat area....does that damage matter? The rest of the bearing looks fine...


The

 

Driveshaft bouncing, hopping? A bent shaft or loose bearing come to mind. I have heard of universal joints having early failure. If memory serves me right, it was an import and had not been heat treated, was soft.
If that full floating differential has run low on lubrication for any length of time, suspect wheel bearings.
A little etching as shown will cause no problems. Have you ever had the rear differential cover off?

 

Yes the rear most drive shaft section has a 3/4" bounce to it. Its going tomorrow morning to the Drive Shaft Pro here to be balanced. No I havent pulled off the rear cover will do so in the morning just before taking the drive shaft....The last thing I did yesterday was to remove the drain plug...So when I go to it tomorrow it should be as empty as it can be..It was still full from my recent refill..this has the full floating axles so the wheel bearings are inboard...big job to pull the carrier etc...oh well...
.YES its been run low...Im an idiot since Ive know that pinion seal has been leaking.......about a month ago I had to add a FULL GALLON of fluid to fill it up...there was 20 shards of 1/4 inch steel debris sticking out straight like whiskers on the magnet for the FILL plug then...I didnt think to photo them of take that to a diff expert to ask a month ago...I figured the damage was done maybe it wouldn't be too terrible....I dont see any debris this time on that top plug and there was none on the bottom drain plug that I hadnt pulled prior....The growl noise I hear doesnt reproduce with the truck on jack stands. I can feel some of the roughness and hear some growl from that rear most center support bearing. The roughness I feel sitting in the drivers seat that happens either accelerating from a stop or coasting or at sustained lower speeds can be felt with it on the stands just not nearly as profoundly....I guess Ill pull those 12 cover bolts and remove the cover to see what I can see...

 

Yes the rear most drive shaft section has a 3/4" bounce to it. Its going tomorrow morning to the Drive Shaft Pro here to be balanced. No I havent pulled off the rear cover will do so in the morning just before taking the drive shaft....The last thing I did yesterday was to remove the drain plug...So when I go to it tomorrow it should be as empty as it can be..It was still full from my recent refill..this has the full floating axles so the wheel bearings are inboard...big job to pull the carrier etc...oh well...
.YES its been run low...Im an idiot since Ive know that pinion seal has been leaking.......about a month ago I had to add a FULL GALLON of fluid to fill it up...there was 20 shards of 1/4 inch steel debris sticking out straight like whiskers on the magnet for the FILL plug then...I didnt think to photo them of take that to a diff expert to ask a month ago...I figured the damage was done maybe it wouldn't be too terrible....I dont see any debris this time on that top plug and there was none on the bottom drain plug that I hadnt pulled prior....The growl noise I hear doesnt reproduce with the truck on jack stands. I can feel some of the roughness and hear some growl from that rear most center support bearing. The roughness I feel sitting in the drivers seat that happens either accelerating from a stop or coasting or at sustained lower speeds can be felt with it on the stands just not nearly as profoundly....I guess Ill pull those 12 cover bolts and remove the cover to see what I can see...

 

1/4" steel shards does not sound like the rear end is healthy at all. Was the pinion tight prior to removing the yoke and bearings? Or was the pinion flopping around enough to appear the driveshaft was the problem? Might be time to look for a complete rear end assembly, one that has not been run dry of lubrication. My SWAG is, your rear end has serious problems. Hope not.
Edit: The axle bearings first to go are usually the outboard bearings at the hub ends as they are the first to starve for lubrication.

 

Yes Pinion was tight It was NOT contributing to the drive shaft hop....I have a 2nd complete rear end of unknown condition...The truck it came from hasnt run in ions. I will pull the cover on this unit in the morning. Take the drive shaft in...then come back to pull Wheels etc off ....Ill eat a steak tonight. Get to bed early. Awake early eat a good breakfast because Im going to be lifting heavy things and dealing with tight things tomorrow....Removing wheels and tires and rear drums ARGH>>>>

 

Gary,

I am not sure I would worry much about the marks on that bearing where they are. I would be more worried about the actual rollers and taper.
Having said that, you probably already know you can buy that bearing from Amazon (and many others for less than $40 (incl shipping!)

You're going to need to probably pull the "pumpkin" and inspect it carefully. There are shims that control the preload (and subsequently the backlash) between the pinion and ring gears that you will want to check. plus, vibration, growling, and other noises are frequently due to drive shaft balance, angle and/or worn U-joints.

If you haven't already, I would just replace all the U-joints and the center bearing.................. And check the angle between the engine, front and rear drive shaft and the rear-end.

Spicer has a good discussion on angles Measuring Angles Spicer Parts

There's a whole lot more for this on the web!

Cheers,

Rick


The spindles (seal and bearing areas) on my Eaton 1350 Housing are not very good.

I am looking for a machine shop up here in the NW that can put the axle in a big lathe so they can weld/flame spray and re-machine the bearing, seal and threads on both spindles.

http://www.axlerepair.com/drive-axle-repair.html

 

Hi Rick...thanks for the reply..I trust you and yours are Well....All of these U joints were installed less than 10,000 miles ago...Also the 2 center support bearings were done then also...yet the rear most support bearing has a groan and probably should just be replaced again......Ill be pulling the pumpkin cover in the morning instead of seeing my customers...those who can be paid to work on this truck...are too busy to do it so Ill have to do it to get it done...I will check the drive shaft angles...it wouldnt surprise me if they arent as steep as they should be...the front two look almost straight...the rear most has a nice angle but like I said everything that has been "professionally" done that I paid a lot of $ for has had to have me go back and do something to actually complete the job...so the guy who put the box on also did the drive shaft work....Ill have the guy balancing the drive shaft verify that the 2 low mileage u joints in that section are at least ok....I still need to do something with these wheels also besides being Widow Makers......the two on the driver side rear wobble side to side like two inches outside the line of what the edge should be....I guess the other truck will have to go on the back burner...I will ck my housings to see how good the spindles housings are----....

 

2) BB-4616-B .. Pinion Bearing Cup, stamped with BIN: 53375 / Obsolete

2) BB-4621-B .. Pinion Bearing, stamped with BIN: 53176 / Obsolete

BIN: Bearing Industry Numbers, used by auto parts stores & bearing shops.

 

Bill thank you for the response...... please pm or email me your physical address...I want to send you a snail mail thing

 

Anyone? 1955 "C" 600 COE..What do I torque the 11/2" nut down to that holds the driveshaft yolk at the pinion bearing? Toque specs for this EATON-FULLER 1350 2speed Differential?...searching the internet to find info like torque specs and the fluid capacity for this 1350 unit hasnt bore any fruit for me.

 

Some axles have an alignment pin on the hub face that goes through a small hole in each rim between two of the lug holes. If the rims are not slid over the pin, what you describe will happen.

 

Thank you...i have checked for improper install of the wheel assembly...specifically a pin not aligned with the hole before and dont recall seeing a pin...i will check again before taking this truck off the jack stands. I found the cause of the hop in the rear most driveshaft section...the front u joint in that rear section had NOT been replaced with the driveline work less than10,000 mies ago. Half of that front u jointe was SEIZED UP!!l Once again I am forced to follow behind someone elses work and fix something they obviously should have done. Who leaves one of six ujoints unreplaced?
Does Anyone know the torque specs to cinch down the pinion bearing nut on this Eaton 1350 2 speed differential?

 

The 1350 oil fill requirement is 15 pints, just shy of two gallons. However, if you have oil lubricated hubs and bearings add 2-1/2 additional pints and follow the axle tilt procedure. If memory serves me correctly, the pinion nut torque is 350-375 ft. lbs. (about four good bumps with a 3/4 drive impact wrench).

 

I just sent you a text with all the "stuff" for a 1350 from my Eaton Truck Axles Service Manual. Torques, oil level, and other stuff is there. Let me know if you cannot read it