what fluid is used in the wheel hub?

[WarRig]

I have a 1078 and have read about the hubs getting hot but I cant find the posts. I got a hold of it last year and the rear hub had a slight drip. It has continued to slowly leak staining the wheel a tad. It gets hot to the touch after driving it and the others do not. The question is can I just fill it and drive it a little or is it the wheel bearing or something else? Additionally what commercial fluid is used to fill the hubs and is it shared with the pumpkin? Do I fill the hub or the pumpkin?

Thanks in advance

 

[Suprman]

Front hubs have their own fluid reservoirs the rear hubs share with their axle. I am swapping mine over to synthetic gear oil.

 

[NDT]

Welcome to Steelsoldiers. I would open the wheel end differential and check all the gears inside for anything abnormal, then reseal the hub using silicone and refill the hub with 85W-90 gear oil. Yes, on the rear axle, the gear oil can travel from the pumpkin to the wheel end if the truck is on a side slope.

 

[WarRig]

That was my 1st post so this is all new to me although I ve been reading the posts for a year. You guys rock with how much you know by the way

so if my rear hub is leaking should I fill it from the hub or from the differentials? also what does the leak indicate a bearing or something bigger.

 

[WarRig]

I have a homecoming parade about 30 miles up the road on Friday, it has run good and I drove it up last year. Can I fill the hub up with the 85w90 and drive it even though it has been getting hot to the touch or is it better to get into it?

 

[NDT]

You fill the hub from the hub fill ports. It is leaking because someone did not do a good job sealing it with silicone last time it was opened. Time to download the technical manuals and do some reading, we don't mind answering questions but you will need to read up sooner or later.
If it was me I would open the hub before I did any long trips like your parade. There is a whole lot going on inside the wheel ends with lots of expensive parts.

 

[WarRig]

Sounds good. I am going to wait and open up the hub with a friend. I have read through the operators manual but am now just getting into the technical manuals.

 

[WarRig]

TM Volume 3 Chapter 10.3 Differential Spider Assembly Replacement. So I will be removing the wheel end hub assembly and check for abnormalities as NDT recommended. I really hope it is just a reseal since I have no idea where to get the internal gears and if they are commercially available. Thanks again

 

[Overdrive]

I put 75W90 Full synthetic oil in my front hubs as soon as I got my 1078 home. Have no hot hubs issues.

 

[Shark Bait]

I put 75W90 Full synthetic oil in my front hubs as soon as I got my 1078 home. Have no hot hubs issues.

That's what I put in mine,mthe 75/90 synthetic is what the TM calls for?

Dave

 

[sargentwolf]

I put Lucas gear oil in the front hubs, 75w. Slightly warm to the touch after a good 20 minute highway run.

Side note, my rear hubs were dry after the gearbox oil change. Refilled them via the rear hub fill ports with cheapo gear oil in rural kings parking lot.... Once the starter is reinstalled, I'll be flushing them again and filling with Lucas.

 

[TNriverjet]

There's a good summary of fluids, capacity and type in the linked google docs spreadsheet in this thread. It lines up with what I found from my recent reading in the TM's. Thanks to Wes for compiling this!

http://www.steelsoldiers.com/showthread.php?155667-LMTV-FMTV-Quck-Parts-Reference-Spreadsheet

 

[f8617]

FWIW -- I believe the hub fill port plug (allen screw) is magnetized...metal powder on the plug usually indicates a problem...parts (shims, bearings, races, seals, CTIS seals) are on eby & SS vendors...a brass/light-weight, drill-mounted wire brush does a good job of cleaning previous silicon sealant off mating surfaces. drivers-side wheel lugs are left-handed threads....

PS -- anyone else bothered by the (seemingly too light) maximum torque of 50ft-lbs on the 3-7/8" wheel bearing nut, and subsequent 90deg back-off, and 30ft-lb final torque?

 

[Ukraine Train]

I'm a little confused... do the rear hubs need to be filled separately or do they just get filled by the differential fluid? I was under the impression that as long as the pumpkin is full then the hubs are ok.

 

[TNriverjet]

I'm a little confused... do the rear hubs need to be filled separately or do they just get filled by the differential fluid? I was under the impression that as long as the pumpkin is full then the hubs are ok.

That's what I thought too after reading the TM's. It is supposed to be a full floating axle in the rear. However, I did notice fill/drain plugs on the rear hubs too. The spreadsheet I linked a few posts back calls out fluid separately for the front hubs and differential. It then mentions only one fluid fill for the rear.

 

[sargentwolf]

Howeve, my rear hubs were bone dry. Maybe the fill port was blocked or something? No idea. But do check yours.

 

[TNriverjet]

I checked the rears today. I put some gear oil in one side then sealed up and headed to the other side. When I opened the plug oil came gushing out. I quickly put the plug back then realized the head pressure from all the oil in the differential and axle was against the second side as it was parked slightly lower than the first side I checked. The rear hubs are definitely lubed by the greater capacity in the rear diff and axle.

 

[Kodyman]

has anyone heard of a hub getting hot from a brake that is dragging? I have a right front hub getting hot, -even after being checked, shimmned. It doesnt pull to one side while driving which would indicate a dragging brake, yet i wonder what else it could be making it hot...

 

[coachgeo]

has anyone heard of a hub getting hot from a brake that is dragging? I have a right front hub getting hot, -even after being checked, shimmned. It doesnt pull to one side while driving which would indicate a dragging brake, yet i wonder what else it could be making it hot...

yes...... this has been reported in other threads that one hot hub is probably a brake issue.

 

[Ronmar]

Hot is such a subjective term. IR thermometers are pretty inexpensive. Get one! A rule I developed many years ago was if I can stand to hold my hand on it for 5 seconds, the temp is below 150F. Dont need to do that any more as I have several IR thermometers...

yes a draging brake would heat the gearcase. Again an IR thermometer, measuring places on the drum like the inside edge, would help to positively identify the source...