First 4x4 front unit bearing replacement.....

[JAG1]

Got it loose with the help of my new air hammer  , but I need to know what the torque specs are for the axle nut (castle nut) and the for the 4 unit bearing mounting bolts on the back side. 

I plan on using copper anti seize on the mating surfaces after cleaning. Does anyone also put a drop under each bolt collar?

 

To get them loose I had to have a 1/2'' breaker bar and add a 3 foot piece of pipe to get them 

 

Thanks for the help.

Edited October 28, 2018 by JAG1

[dripley]

I never had any trouble with getting them apart except the first time. I dont remember the bolts being terribly difficult the first time and definitely not difficult since then. I have had mine out on 3 occasions since and has been a piece of cake.  I put anti seize on the unit bearing but thats all. I dont remember the torque values however.

[Dieselfuture]

I did 180 on big nut and 125 on 4 bolts. I think that right for 2nd gen

Did your bearing get lose or somet noise when driving? Can't remember, I think you mentioned something before

[JAG1]

40 minutes ago, Dieselfuture said:

I did 180 on big nut and 125 on 4 bolts. I think that right for 2nd gen

Did your bearing get lose or somet noise when driving? Can't remember, I think you mentioned something before

I cooked the brakes on my last trip down south. Came down from 8,000 ft to about 2,000 ft in about 4 miles. They got hot and I think I cooked the grease in the unit bearings since one went out shortly after  and just 99,000 miles. No warning, just hair raising moments getting off the road. So I'm going ahead and change out the other side for reliability.

 

Dripley, on my 4 bolts they were so tight it sounded like they broke off  for sure when using almost 4 foot long bar. I feel lucky.

Edited October 28, 2018 by JAG1

[Mopar1973Man]

6 minutes ago, JAG1 said:

I cooked the brakes on my last trip down south. Came down from 8,000 ft to about 2,000 ft in about 4 miles. They got hot and I think I cooked the grease in the unit bearings since one went out shortly after  and just 99,000 miles. No warning, just hair raising moments getting off the road. So I'm going ahead and change out the other side for reliability.

 

Good reason for an exhaust brake. 

[JAG1]

I heard no good on an automatic trans.

 

So glad I'm learning how to do this. With the same two trucks and shops wanting $450. a side..... forget that. Napa wanted 300 bucks just for the bearing. Got it from Amazon for 204. The wholesale house wanted 240 . Should get a price from dealer just for amusement 

Edited October 28, 2018 by JAG1

[Mopar1973Man]

15 minutes ago, JAG1 said:

I heard no good on an automatic trans.

 

Either modify the transmission to get lockup in 2nd and/or use an exhaust brake made for the 47RE. All current PacBrake's will give at least lock up in 3rd and 4th gear. @Dynamic has a way to get lockup in 2nd Gear. 

[dripley]

19 minutes ago, JAG1 said:

Dripley, on my 4 bolts they were so tight it sounded like they broke off  for sure when using almost 4 foot long bar. I feel lucky.

I have had several bolts I removed for the first time that have sounded like that thru the years. Even some that I reinstalled and removed later. 

[JAG1]

I got it all back together and tightened everything like DieselFuture said but had to use a chinese made cotter pin. Sheesh.

 

Anyway with the bearing off I can feel a rough spot in the bearings when turning in your hands. Thanks to MoparMikey again for saying to go and replace the other side.... he was right again. I travel long distances with this truck too 

[Dieselfuture]

One thing on the axle nut, every time I went to 180 my cotter pin was too far off, so I found some big washers I had and tried diferent ones till I got close. Instructions say go 180 and then keep going to closest hole but if you're to far off by the time you go to closest hole you may increase another 50 lb, and I believe it does effect bearing pre-load a little, maybe not. But if you look at bearing it doesn't just bottom out on flange, there is a little gap, so I think it's possible to over do it. 

[JAG1]

Thats good advice since I was thinking it does bottom out. I went a bit tighter to get the cotter key, I will check on that .

 

On second thought DieselFuture, doesn't the axle nut pull the shaft into tight to the bearing, so no gap?

Edited October 29, 2018 by JAG1

[Mopar1973Man]

Just trying to pull my driver side unit bearing off yesterday resulted in about a 4-hour battle. The Air hammer tool did not work. I spent a majority of time smacking that bearing with a 6-pound hammer to get it to even move. Spray the gap down with PB Blaster and let it soak in smack it some more to even get it to move. I ran my compressor so long I was blowing the breaker trying to get it to move. 

 

Now the reason for this is the fact this is the bearing that failed last year I replaced at a friends shop in Marsing, ID. When I did I didn't have access to anti-seize and other materials. It was installed clean and dry. The salt and MagChloride have played their roll and made this unit bearing nearly a solid piece with the knuckle. 

 

Not to hijack @JAG1 thread... 

 

Now the reason for the unit bearing to be removed was to do the wheel joint on the driver side. It was a factory wheel joint. (356k miles and 16 years). I couldn't get the clips out let alone move the bearing caps. I finally gave up at 4pm and called a friend in New Meadows, ID that has access to a 100-ton press. Needless to say, using about 20 to 30 tons of pressure to get the bearing caps to violently jump to even move. I would of never got those bearing caps out with a 6-pound hammer...

 

Moral to this post... Just because you can install or have parts that can last 300k plus miles. I highly suggest against doing it. It will require even more effort to removing a part that has been installed in the suspension or axles for over 16 year and 300k miles. Make sure to use lots and lots of anti-seize on all parts and bolts! 

Edited October 29, 2018 by Mopar1973Man

[JAG1]

No hijack.... that's good information. Like DieselFuture The more we get after these things the better truck you'll have. Even to the point of being more reliable than anything else. Again, I thank you for telling me to replace the right side bearing after left side went out. I really think they went bad from sitting too much all winter as the truck has only 99k on it.

[Mopar1973Man]

2 minutes ago, JAG1 said:

I really think they went bad from sitting too much all winter as the truck has only 99k on it.

 

Well, you better be careful the new bearing might be sitting on a store shelf too long.  Bearing and the grease are not affected by storage. The grease lifespan is affected when excessive heat is applied like you hard braking down long grades. The bearing lifespan is affected by tire size and excessive wheel offset.

 

The only thing that can be affected by weather and time is the seal that keeps water and dirt out of the bearing if the bearing seal fails then the grease will be contaminated with water, salt, MagChloride, etc and then the bearing life is shortened. 

[JAG1]

That's right.... I sometimes worry about not driving and letting it sit too much, but your right I did cook those brakes bad enough to be smoking when I stopped. It might be the back brakes need attention and may have contributed to relying too much on the fronts. Thats my next project and enjoy the fact they are disc brakes in the rear. Will make it easier.

[Mopar1973Man]

5 minutes ago, JAG1 said:

That's right.... I sometimes worry about not driving and letting it sit too much, but your right I did cook those brakes bad enough to be smoking when I stopped. It might be the back brakes need attention and may have contributed to relying too much on the fronts. Thats my next project and enjoy the fact they are disc brakes in the rear. Will make it easier.

 

The other thing is once you got them that hot to things are going to be done. Replace the brake pads they are not designed to be cooked like that and pads will most likely fail later. The second thing is the rotors are not designed to be cooked either and you most likely have warped rotors now and take way too much to turn them true again. Other things impacted by the heat is the caliper pistons and the caliper seals. The pistons will cake up brake fluids as it heated and harden to the piston. The seals are only rubber and only can take so much heat. The brake fluid as well I would wonder what its condition is too.

 

[JAG1]

Yep I need to do all of that and I am glad you made mention of that. All because it was 105 degrees in the valley I wanted to camp at the 8,000 ft level.

[Mopar1973Man]

On 10/29/2018 at 10:45 AM, JAG1 said:

Yep I need to do all of that and I am glad you made mention of that. All because it was 105 degrees in the valley I wanted to camp at the 8,000 ft level.

 

The best thing to do is lock it down in 1st gear. Turn on your hazards and crawl off slowly just like a truck would. 

[Russ Roth]

On 10/28/2018 at 7:54 AM, Mopar1973Man said:

 

Either modify the transmission to get lockup in 2nd and/or use an exhaust brake made for the 47RE. All current PacBrake's will give at least lock up in 3rd and 4th gear. @Dynamic has a way to get lockup in 2nd Gear. 

 

He can also set it up to lock in first gear too.   Mine is that way as was the first one he built for me. I also had first gear lockup on the OEM trans in the '01 with the Dunrite VB I had.  I have a couple places I use it with the toy hauler and very slow going due to rough and steep old logging roads.  Very useful for me.  Just don't let it shift 1-2 locked as it will knock your socks off with a triple disc convertor.    2-3 is ok as long as you are under load and power and 3-4 always works good locked unless you back off to very little throttle then it has a kick,

[Mopar1973Man]

Heck even my 96 Dodge 1500 has a good kick when it shifts 2-3 gear change.