I have been experiencing a rear axle noise when driving.  The noise occurs only under acceleration (light or heavy).  It is a steady whine that changes in pitch with vehicle speed.  The noise has become more prominent over the last several months.

 

I disconnected the driveshaft and I can move the pinion shaft by hand up and down and side to side a small distance.  My understanding is that there should be no free play here.  I also removed the differential cover and drained the oil.  There was the normal amount of fine filings on the magnet, but there were no chunks or pieces of metal in the bottom of the housing - in fact, it was very clean for the miles (386,000 miles).  The ring gear shows a normal wear pattern and the teeth surfaces do not appear to be worn.

 

According to the FSM:

 

 

I am inclined to believe that I do have a worn rear pinion bearing because of the pinion shaft movement and the symptoms match the FSM description.

 

The knowledge (and tools) needed are far beyond my skills for a differential repair on the Dana 80 axle.  Can anyone recommend a competent differential repair shop in the Boise, Idaho area?

 

Any thoughts or suggestions are welcome.

 

- John

Edited April 16, 20241 yr by Tractorman

@Tractorman knowing you close to me. You could try Idaho Drivetrain in Boise Idaho. I'm not sure if they could repair axle or if will they just swap axles. 

 

https://idahodrivetrain.com/

 

(208) 475-2774

I've done a few pinion bearings in Dana rear axles and they aren't that bad.  You'll need a spreader to get the carrier out and back in, a big hammer to knock the pinion out of the front bearing/housing, a press to remove and install the rear pinion , and a big torque wrench.   There will be a shim under the rear bearing, just reuse it when the new bearing is pressed on to the pinion.

Thanks for the information.  How heavy is the differential?  I don't have a lift, so I would have handle the weight from underneath.  It would seem that much weight could be awkward to handle.

 

Just not sure I would want to take on the task, especially if I found other worn parts.

 

I talked to the owner of Jim's Drive Train Specialties in Boise.  He gave a ball park figure of $1200 - $1400 to R&R the pinion shaft bearings (including parts) as long as everything else is okay. 

 

- John

I never had to R&R the whole axle assembly to change bearings.   Jack the back of the truck up and put jack stands under the axle.   Now remove the cover and drain the housing.  Remove the driveshaft and the pinion nut; I always market the flange and pinion, so they go back together the same as they came off.     Remove the rear tires and axle shafts.   Install the spreader, remove the carrier bearing caps and remove the carrier; be sure to mark the carrier bearing caps so they go back the same as they came off.   With a mallet and a block of wood beat the pinion out of the housing.   The front bearing should come off and the rear bearing can be pressed off and the new one pressed on.  Remove the old races out of the housing install new bearing races, pion and new front bearing.   Inspect the carrier bearings while out of housing.   If they are bad press them off keeping the shims to back on to the same side they came off and press on the new bearings.  Put the carrier back in and torque everything to specs.

 

I've replaced whole rear axle assemblies in Volvos and Chevy Astro vans jacked up off the ground with a floor jack and another person to help man handle the unit.  It's not hard to do.

Edited April 17, 20241 yr by IBMobile

Thank you for the great detail.  Just for clarity, I was asking about the weight of the differential carrier, not the axle housing.  Since I have never done this before, I was wondering how difficult it would be for one person to lift and guide the differential carrier into place from a creeper on the floor.

 

I appreciate your information.

 

- John

Can you bench press 50 pounds?

Tool needed to get the carrier out and back in is a rear axle spreader

https://www.vevor.com/differential-housing-spreader-c_10334/dana-spicer-differential-housing-case-spreader-dana-30-44-50-60-70-80-p_010780674643?adp=gmc&utm_source=google&utm_medium=cpc&utm_id=21040685019&utm_term=&gad_source=1&gclid=CjwKCAjw5v2wBhBrEiwAXDDoJW0ujeO9IT-MqMJpUAHGEaiOTnYXBl9kzBajCLoWtsREe5IpPrxQSxoCRycQAvD_BwE.

I had looked at that very same spreader and a suitable bearing press tool as well. 

 

I have decided to go with Jim's Drive Train Specialties in Boise.  I have already spoken with Jim and hopefully just new pinion bearings and a seal will fix the problem.  If more parts are needed (along with the technical skills to replace them), then at least the truck won't be sitting disabled in my shop with me scratching my head.

 

@IBMobile, thank you for the information you provided.

 

- John

Edited April 17, 20241 yr by Tractorman

Just a followup. Jim's Drive Train Specialties finished the repair on my truck on two days ago.

Jim's crew installed a Dana 80 differential overhaul kit which included axle shaft bearings, pinion bearing and pinion seal. He said that visually the ring and pinion gear looked to be in very good condition. However, after setting up the gears and checking the pattern, he said the pattern was where in should be, but there was some wear on the ring gear. He said that it would not be a problem, but it will be noisy - just not as noisy as it was before the repair. It turned out not to be noisy at all - quiet under all operating speeds on the 150 mile trip home.

I am very pleased with the service from Jim's Drive Train Specialties. If anyone is needing drive train or axle work done in the Boise, Idaho area, I highly recommend these folks.

 

- John