1947 Mack model 45 rear end specs/questions.

[dlerdmann1185]

I’m currently in the process of restoring a model 45 that has been sitting in our fire departments storage for quite some time. I’ve had to completely remove and  disassemble every component of the braking system due to leaks and corrosion issues in the hydraulic components. In doing this, I obviously had to remove all the wheel assemblies. When I popped the passenger rear axle loose, a small amount of gear oil ran out. I popped the axle back in and proceeded to drain the gear oil. I removed the fill plug first and stuck my finger in the hole and didn’t get any fluid. I pulled the drain plug and got about 4 quarts out of the chunk. I removed the axles and wheel assemblies and found that the bearings were packed with bearing grease, but there was also gear oil mixed in with the grease. My question is, were the rear wheel bearings originally wet bearings or did someone previously pack the bearings with grease by mistake? I also need to know the type of gear oil used in the rear end. Thank you for any help you might be able to provide.

[609albert]

try posting your question(s) on the Antique forum for more response 

[yarnall]

I have a 1951 405A.  I believe the rear bearings were on grease and my father converted them to oil. I will try to remember to ask him. My father has a 1941 Type 45 and 55 but we have not had them apart yet.  Michael. 

[Vladislav]

I have a 1945 Mack truck (tandem rears) and its bearings designed to spin on grease. But there are additional seals in the jack shaft flanges to separate gear oil from the bearings. So my suggestion is your wheels spin on oil. Or maybe the outer seals also took place and someone removed them in the past. To be sure I would look in a E-model parts list or maintenance manual for the hub assembly design.

[dlerdmann1185]

On 6/30/2021 at 8:10 PM, 609albert said:

try posting your question(s) on the Antique forum for more response 

Will do. Thank you 

[dlerdmann1185]

On 6/30/2021 at 9:38 PM, yarnall said:

I have a 1951 405A.  I believe the rear bearings were on grease and my father converted them to oil. I will try to remember to ask him. My father has a 1941 Type 45 and 55 but we have not had them apart yet.  Michael. 

Thanks for the info 

[dlerdmann1185]

On 7/4/2021 at 2:10 PM, Vladislav said:

I have a 1945 Mack truck (tandem rears) and its bearings designed to spin on grease. But there are additional seals in the jack shaft flanges to separate gear oil from the bearings. So my suggestion is your wheels spin on oil. Or maybe the outer seals also took place and someone removed them in the past. To be sure I would look in a E-model parts list or maintenance manual for the hub assembly design.

Thanks for the info 👍