[Marc-Andre Holtewert]

Hallo,

i´ve bought a Set of Yukon free spin hubs YA WU-07 from my friend for my Wrangler TJ Rubicon. Now I have some problems with the installation. I´m not sure if in the official manual the bearings in the explosion chart are on the right position.
I hope somebody can explain me on the hand of the pictures with the respective numbers what is the right installation position for the bearings and the(rubber)seals. I attached some photos, please have a look and tell me what are the right positions.
Also there are on one side some broken wheel studs, what are the right ones that I must have and where can I buy it? I´ve searched these ones. Dorman 610219 Did they fit in the hubs?

 

[Mouse]

Marc, I have not used these hubs. Welcome to ROF. Hopefully someone has experience.

 

[johncanfield]

Welcome Marc. I don't recall anybody here tearing into a Yukon hub but maybe somebody has. You could try calling or email Yukon for assistance.

Those are great pictures of the parts, well done.

 

[BobsLJ]

Unsure about the seals. I would imagine Yukon would be able to supply install instructions.
Bearings go on like pic 1. They are tapered roller bearings and also require grease.

 

[Scotty]

I know this thread is a few years old, but any gain in MPG? I’m thinking of doing it…

 

[johncanfield]

I can't imagine much if any fuel savings since you are just disconnecting the wheels from the drivetrain.

 

[Scotty]

I can't imagine much if any fuel savings since you are just disconnecting the wheels from the drivetrain.

How can that be? I’ve always assumed that with TC in 2WD that the “disconnect” is inside the TC itself, causing the forward motion of the vehicle to turn the front axles, differential and front driveshaft.

 

[Norminator]

I believe the Rubicon has a full time transfer case and there are components that provide needed resistance, that if disconnected would shorten the life of the transfer case.

 

[Scotty]

I believe the Rubicon has a full time transfer case and there are components that provide needed resistance, that if disconnected would shorten the life of the transfer case.

I thought the oil pump was driven off the rear output shaft?

 

[Norminator]

The research I saw said resistance was the relevant issue.

 

[Scotty]

Do you have a link to that Norm? Now that I’ve heard this I have to get to the bottom of it one way or the other before I buy it. This is why I joined here to get info, thanks!

 

[rlenglish]

Jeep/Dodge/Ram have had axle disconnects off and on throughout the years. You are right that locking hubs will stop the front driveline components from turning but any mpg changes would be minimal at best. Installing locking hubs do have some advantages but they also need regular maintenance.
If you were to remove your brakes you can turn your front driveshaft and front diff gears by hand without much resistance. It is such a small amount compared to how much force it takes a Jeep to cruise down the road at 60 mph.
I do not remember any TJ that came with a full time transfer case? They are all part time or full disconnect?

 

[rlenglish]

Bearing pic 1 good, pic 2 bad. the bearings should have mating races in the rotor adapter. Rubber seal fits into the new extension housing like pic 1. there should be another bearing inside there to pack with grease. The flat part of this seal sits against the small bearing. The plastic washer goes against the axle like pic 1 and the rests against the seal. Flat part next to the seal and chamfered part against the axle. All of it gets packed with grease.

 

[rlenglish]

Looks like Yukon supplies wheel studs with their kit. Might be best to contact them. It could be the same as factory or a special one off.

 

[Norminator]

I report on what I’ve learned to test what’s being put forth about something, in your case locking hubs. I don want to link to untested information, although it was from a mainstream Jeep source. Listen to rlenglish. I’ll follow up on the discrepancy.

 

[johncanfield]

I thought the oil pump was driven off the rear output shaft?

If your comment is about transfer case lubrication - I believe the transfer case is just splash lubrication - in other words lubrication is not pressurized.

If you would, tell us what your experience is with Jeeps, old or new. Do you want to off-road, rock crawl, or do expedition camping

 

[Scotty]

John,
The 241J / OR / Rocktrac TC has an integral lubrication pump that draws ATF+4 (owners manual recommended fluid) from a pickup tube located in the lower left section of the case as viewed from the rear. This pump is concentric to and driven by the rear output shaft. It’s probably safe to say that the chain slings oil as well.

This is my first Jeep. As with probably the vast majority of Jeep owners, this vehicle is currently used as primary transportation with less than 1 percent of its mileage being off of a paved road.
Most of my off road use is on gas pipelines, electrical power lines, fire roads and bushwhacking. I have climbed the outside edge of Jeep-eater/MaBell in western Massachusetts.

I’ve been corporate aircraft mechanic since 1983. Mechanically, my TJ is child’s play in comparison.

 

[Norminator]

I think I found the confusion on the “full time” transfer case thing. Newer Rubicons have an auto 4wd high selection where we older TJs have to manually move to 4wd high. Apparently it’s called a full time 4wd system. They’ve got auto everything these days.

I looked all over and I can’t find anything, but minimal mpg improvement for locking hub conversions. There’s lots of banter on maintenance with or without. I replaced my original unit bearings not to long ago and I’m up to 170K. I didn’t raise a finger to maintain them and I ran 33s with wheel spacers. If anything, I maintained them with dirt and grime and had a blast even going beyond my equipment or ability.

 

[elff]

@Norminator That is an option which costs extra. I did not add that to my Gladiator build, so I have to engage 4HI in the GLadiator just like I do in the TJ.

 

[Norminator]

Thanks for shedding light. We’re not in Kansas anymore Dorthy. Interesting stuff.