Correct assembly of rear hubs

[JJump]

I'm in the process of chasing down a brake fluid leak - I've added about a pint of fluid over the last 3 months. The right rear wheel was suspect because of some sort of leak. Turns out the leak was gear oil caused by what apears to be a rear seal that was installed backwards. So for a sanity check, I have a couple questions... .



1) Should the hub seal be installed so that the lip faces outboard, i. e. , towards the bearings vice towards the brake shoes?



2) Are the hub bearings lubricated with grease vice gear lube? When I pulled the axle shafts an ounce or less of 90 wt was in each of the bearing cavities but any signs of axle grease were not apparent on the bearings.



3) Does the presense of gear oil in the hubs indicate an over full condition?



Thanks for the help!

 

[JJump]

And I forgot one more... .



4) Does anybody really torque the lug nuts to 300+ ft-lbs as suggested in the owner's manual? What's a good number?

 

[Philip]

#1 The lip should be towards the bearing.



#2 The bearings are lubed with axle gear oil. one ounce was low.



#3 It was not an overfill condition. The full level is above the axle tubes to provide

lube to the hub bearings.



#4 Yes. I use an IR impact wrench rated to 300 ft. lbs to tighten the lug nuts on

my truck.

 

[cerberusiam]

As a rule the lip seal goes towards the lubricant you are trying to keep in. Most of the good seals will have 2 lip seals. One to keep lubricant in and one to keep the dust out. Almost all seals will have a spring on the lip that is used to seal the lubricant in and no spring on the dust seal. Check the spindle where the seal rides and make sure it is realtively smooth and no grooves in it. The seals will eventually wear a groove and won't work correctly even when new.



The hubs are lubed with same gear oil as the diff. Some will lube the bearings with grease when they are put together so there might be grease in addition to the gear oil. Generally driving will keep gear oil moving outwards to the hubs and keep them lubed so keeping the diff topped is important. An ounce draining out of the hub is a bit low.



The studs should torqued to the correct number. Just keep in mind you may need a fairly large bar to bust them loose if you ever have to change a tire and according to Murphy's law it will be the middle of the night, snowing, and 50 miles from anywhere when it happens.

 

[Lock93]

Good question.

Wouldn't the type of wheel your running change lug nut torque requirements? I'm pretty sure my alum wheels won't tolerate 300 ft. lbs. I want to say the tire dealer said 110 ft. lbs (but can't remember right now; wrote it down and paper is in my truck). Perhaps 300 for the factory steel wheels only?

 

["Mad Max"]

That's a REALLY good question about the dually aluminum rims. Hmmm, have to call my wheel bubba about that one. Is it a 'dually' thing (ie: number of wheels) or a 'torque/weight/hauling' thing?. I have a set of Eagle Alloy dually rims... . hmm, this I havta' know.

- Sam

 

[TMWeber]

I've always done 125# on the rims and recently was told 110# -? Sorry, don't mean to highjack the post.

 

[Philip]

I run the factory torque settings on my American racing alumn rims on my dually. I tried the lower torque settings once and had one set of duals comes loose. So now they get full torque. Been running this way for almost 10 years on two different dually's.

 

[Philip]

One thing I forgot to add was check the area of the axle tube where the seal rides. If there is any wear at this point install a speedy sleve to stop a future problem of seal leaking.

 

[DKasper]

All the guys are right on with their comments -- I'll add that in the past if there has been a groove where the seal rides and I can't get a speedi-sleeve, like Phillip recommended, I have installed the seal backwards so the lip is not in the groove and everything sealed up great until I could get back in and repair properly.



I torque my Alcoa wheels to about 200 lbs. -- I do the stock steel wheels to the recommended 300 lbs. Haven't had any problems -- I'm just a little nervous putting that much torque on the aluminum wheels. Sam, let us know what you find out!

 

[JJump]

Thanks for the inputs. The seal surfaces looked ok, i. e. , no grooves, but I went ahead & buffed them out with some 320 grit emery cloth.



When I first got this truck one tire had a slow leak. I took it to an auto tire shop to get repaired, but when I asked them if they had the tooling to handle the torque, they didn't believe me until I showed them the spec in the owners manual. They said all they ever used on heavy duty applications was 125#. I went to a shop that specialized in dump truck & semi tire service & they told me about the same thing. I have a special lug nut socket thats used with a 3ft long breaker bar (came with the truck). I'll tighten them up with that so I will be able to get it apart on the side of the road.



For those with aluminum wheels, I'd recommend talking to the wheel manufacturer.



Thanks again for the help!!!

 

[JJump]

One last note. Paging through the owners manual I came across a paragraph that recommended "repacking" the rear axle bearings when checking the brakes. It didn't mention with what - I assume wheel bearing grease & that' what I used. Also noted that the owners manual recommended filling the rear axle to 1/4" below the inspection plug. I checked the level of gear oil in my arear axle with a piece of bailing wire bent at a right angle - right at 1/4" below the plug.

 

[tugboatphil]

JJ,



I have no way of measuring torque on my impact wrench, so I just turn them until they don't. First time I had to take one loose without the impact wrench, it took a 5 ft piece of pipe on my breaker bar to get them loose.

 

[Philip]

JJump. The packing they are meaning is wheel bearing grease. If you do not plan on jacking both sides of the axle up to run fluid into the hubs after reassy. Then packing the bearings will get them by till the oil travels out to the hubs on its own.

 

[dpuckett]

Looks like all the bases have been covered. Did you get it all back in there ok?



I fill my rear diff to the bottom of the fill/ check plug. I know, the manual says 1/4" below, but the capacity is a little low, IMO, esp those of us who tow now and then (10-15round bales of hay, personally), so I just fill 'er up, and keep the vent good and cleaned out. I have been running Mobil1 75-90 synthetic in it for almost 50K; so far, so good.



Daniel

 

[JJump]

Everything all buttoned up & back on the road. Probably will add a bit more fluid to the rear axle to keep the bearings well lubed. Found the brake fluid leak too - it's dripping off the bottom of the brake booster. It apears that its leaking past the piston seals, but the sides of reservoir seems somewhat damp too, so it may be the reservoir cover gasket leaking. Been too busy the last few days to attend to it - I've been tuning up my 1970 Commando for a motorcycle campout/tour through Madison, Iron, Reynolds, Dent, Crawford, and Washington counties with the local Norton Owners Club this weekend! Wahoo!!!

 

["Mad Max"]

Well fellas - I called the dealer where I bought my Eagle Alloy dually rims, and according to them the lugnut torque is based on the stud length and thread pitch and not the wheel (aluminum or steel). That said the correct lugnut torque for a 93 D350 dually (Dana 70) with steel or aluminum rims is 160 lb/ft.

... . that's all I could find out, but it sounds logical and legit to me... . 160 is a bunch - I don't think I'd have any heartburn with that spec.

- Sam