I just had my Hubs replaced on my 2003 F250. The shop installed Warn 11690 Manual Hubs. The truck has Electronic Shift on the Fly. The OEM Hubs had Locked/Auto positions, the Warn has Locked/Free positions.

With the OEM hubs in the "Auto" position, I could engage the hubs inside the cab by selecting 4x4 Hi or 4x4 Lo.

With the Warn 11690 hubs, can I engage 4-wheel drive in the "Free" position when 4x4 Hi or 4x4 Lo is selected inside the cab? If so, how?

Thanks in advance if you can help with this question!

 

No, the Warn hubs are manual , so they can only be locked in by hand by turning the dial.

You might need to plug the vac line going to the hub, but I'm not 100% sure on that.

 

Thanks Texas_tech Diesel! I had the selector in "free" and tried to engage 4WD inside the cab. It sounded like it was trying to engage, there was a gear meshing sound but it didn't engage so I quickly put it back in 2WD. I'm assuming that your plugging the vacuum line is targeted at preventing it from even attempting to engage on the fly, is that correct?

 

Yeah, that's a bad idea. Basically the front axle internals were not even close to being up to speed, and you tried to engage the transfer case with drastically different shaft speeds. Not a great idea, I wouldn't recommend doing that again.

Not really, that's really just to make sure there isn't a leak in the vac system caused by the manual hubs not sealing like the old ESOF ones did. These Warns don't have any way to lock in other than the dial, they are entirely separate from your 4wd system now. Unless you manually turn them to Lock, you cannot use 4wd at all.

 

the way I am reading this you can switch the **** in the cab from 2wd to 4 high, at any speed up to 55 mph. (per my owners manual) HOWEVER in your case that just engages the transfer case and drive linkage BEFORE the hubs. if your hubs are in free you are in 2wd if your hubs are in lock you would be in 4wd. if hubs are in lock, and you switch back to 2wd then you disengage the transfercase and drive components, but hubs will still put increased drag and maybe a little noise. Alot of people in the winter or when ever 4wd might be needed will lock the hubs and stay in 2wd until they need 4wd. anyway I dont see where what u did will hurt anything.

 

Ok, I'm just gonna break this down real careful like, because I tend to say confusing things, and I just want to make sure no one gets any wrong ideas. I’d hate to hear about someone grenading a t-case over my confusing statements.

There are four (4) components that are important in this situation: the transfer case, the front axle internals, the hubs, and the vacuum system.

In the OP’s case, the vacuum system does not matter anymore. The previously installed ESOF hubs use pulses from the vacuum system to lock and unlock in the “auto” setting. In the lock setting, the auto hubs are engaged, regardless of the state of the rest of the 4wd system. By plugging the vac lines, you ensure that the rest of the vacuum system operates normally, and since the new hubs cannot in any way use the vac system, you aren’t affecting the new function of the 4wd system.

The new hubs are manual. There is a lock and an open setting. Lock is locked, open is unlocked. This means that in the lock setting, the internals of the front axle are engaged, meaning the front axle is moving as the same speed as the rest of the driveline (for arguments sake assume this is true, forget about differentials and small differences in shaft speeds). In the open setting, the front axle internals will not be moving at the same speed as the rest of the driveline. With manual hubs, the truck must be stopped to switch them from open to lock. Putting the hubs into locked and open does not change the truck from 2wd to 4wd, only the transfer case locking the front driveline to the rear driveline will do that. Putting the hubs in locked allows for 2wd driving with the possibility of using 4wd if the t-case is engaged, the hubs in the open position force an unchanging 2wd situation, regardless of the t-case being engaged or not.

The movement of the front axle internals is vital to successfully engaging the transfer case. The transfer case (on the SD, it’s a chain driven model) runs off the rear of the transmission, and causes the front drive shaft to spin when engaged. This is where the situation can go one of two ways:

1) If the front hubs are locked, the front axle internals, and thus the front drive shaft are spinning at pretty much the same speed as the rear driveshaft and axle. Meaning the internals in the transfer case are pretty close to synced. This is when you can engage the electronic shift-on-the-fly system, at speeds up to 55mph, because the front axle is already up to speed. Under the old system, the front hubs would lock in using the vac pulses, bringing the front end to speed, then the t-case engages. With the new manual hubs, the hubs must be in the locked position because the vac system cannot lock them in.

2) The second situation, the “bad one”, is when the front hubs are unlocked and the front axle internals are not up to speed, and the t-case attempts to engage. If the system even lets the t-case engage (I’ve never experienced an electronic case with manual hubs personally), this is when angry meshing noises and ratchet sounds come out from the front driveline. I’ve experienced this personally one on occasion with a manual t-case in an old Bronco.

As for hubs “dragging” and killing gas mileage, I don’t buy into this idea at all. The front axle won’t add a significant amount of HP to the engine load, and really doesn’t affect normal driving at all. I’ve seen plenty of trucks that have had hubs (auto and manual) locked in for the entire life of the truck with no problems. It’s actually a good idea to lock them in and get the axle moving every once in a while to make sure the axle keeps functioning normally.

Finally, my last bit. With truly manual hubs, like the OP installed, you can now access 2wd-Lo. Basically, you put the t-case into its low gear (2:1 reduction I believe), and since the front end is not locked in, you can use this low gearing to help move heavy trailers, back up inclines, and do lots of low speed tasks where more engine power and less speed is needed, but using 4wd would place undue stress on the drivelines (sharp turns, etc). Since certain conditions must be met (ie brake on, tranny in neutral, truck stopped) to get the electronic case into low range, this is a fairly safe practice.

 

Would you like to sell your old auto hubs? If so, how much?

 

very good explination. I stand corrected.

 

You were right on, up to this point.

On the ESOF system, when you move the switch to 4x4, the first thing that happens is the transfer case engages and spins up the front driveshaft. The transfer case gears have synchro's that allow this to happen. Once the computer determines the transfer case is engaged, then it uses the PVH solenoid to lock the front hubs.

 

I'm not calling you out on anything, just really confused how what you said applies to what the OP said he experienced.

Why did he hear a meshing sound from the t-case when he shifted into 4Hi? If the shift order is t-case then hubs, he should be able to shift from 2 to 4 on the switch without hearing anything, which is not the situation he described first hand. Are you saying he should have just ridden out the meshing noises and it would have locked in eventually?

With his open hubs he is mimicking the Auto position on the ESOF hubs before the vacuum pulse, so following your timeline his t-case should have successfully engaged without any problems, then the high pressure vac pulse would not have been able to lock the hubs in, but that really wouldn't have mattered since at that point the front axle would be locked in and up to speed and tied to the rear driveline, just the hubs wouldn't be locked. This should be an Ok setup while driving, I've used 4wd with unlocked hubs on manual systems before, no there shouldn't be problems in the short run, at least in the first few seconds, and enough to cause the noise he heard.

He specifically said he heard meshing noises when he flipped the switch. I guess in my mind if the t-case is always the first to engage in every ESOF system, and that brings the front axle to speed, then why does my ESOF case shift smoothly with no noise, case coming to speed before the hubs lock, and his doesn't? There has to been a speed differential problem inside the t-case to get what he described, and what you're saying is the t-case should have overcome that on its own. Real world vs. what should happen doesn't make sense to me in this case.

 

I can't explain the OP's experience. I'm going off of a couple things. One is what I read once in my online service manual about how the ESOF works. It described the system pretty much how I described it. Unfortunately I can't seem to find that same writeup again. The second is the logistics of bringing the front driveline up to speed while driving at speeds up to 55 MPH. The only way that can happen is via clutch based synchronizers. I just don't see room in the front hubs for synchro's. There are synchro's in the transfer case however. At least, as best as I can tell from the exploded parts diagram.