ok i have a quick question for you guys. i did a search and came up with some good info about the 4x4 in these trucks but noting solid on what i need. I looked at a truck last night. I took it for a drive and on the fly engaged 4x4. Everything came on fast could feel the front wheels pulling. Came to a stop. put in in neutral pressed in the brake and engaged 4 low. it made a clunk? i assume that is the servo on these trucks? ran good in 4 low. took out of 4x4 and i brought it back to the place. i came to a stop and again went to put into 4x4. it would not engage 4x4 high or low at a stop. does the truck have to be moving to engage 4x4 high or low?

 

I don't have a technical answer, but on my truck every now and then you have to move a little for it to engage. I did have a problem about 1 year ago that the servo motor stopped working and I couldn't shift at all. But other than that it seems kinda of normal to have to move a little for the transfer case to engage, but you shouldn't have to be driven down the street though.

Todd

99.5' F-250SD 7.3, 6637 Filter, 50hp Hypertech Program, 4" MBRP Turbo Back

 

yeh thats what we had to do on this truck was drive for it to engage. if you put back in D and drove then turned switch from 2x4 to 4x4 it would engage but you would think that it should be able to engage from a stop as well.

 

ok i called a few fords and spoke with some techs. they said the truck should show engaged in 4x4 in park whether the truck is running or not in drive neutral or reverse. it engages into 4 high while driving and also engages into 4 low when i come to a stop. wha could be wrong. i really like the truck and am just trying to figure out if this will be an easy fix.

 

To start off, the auto 4x4 is engaged by vacuum to the hubs from the solenoid on the passenger side fire wall. You can not engage the 4x4 without the truck running. The vacuum pump will not run without the switch in the on position.

Yes, your truck will engage the 4x4 while not moving, if there is nothing wrong with the system. To go to 4x4 low, you need to stop, put in N and have your foot on the brake. It could take up to 40 seconds to engage to low. Low is not shift on fly.

This is something you should do every year. http://guzzle.rbmicro.com/allube.html

If you have any more questions, just ask.

 

yeh i know it has to be put into the accessory position to engage and the truck engages 4 low also. the thingit doesnt do is engage into 4 high when at a stop in any gear. when the truck is moving i can shift into 4 high on the fly.

 

Sounds like the ESOF hubs...might need to be serviced (see the link provided earlier). Sometimes...if the gears in the hub are not prefectly lined up...they will not engage until moving. The hubs might be a bit dry...and need a fresh application of grease.

That is why...most folks recommend keeping the hubs in the "LOCK" position for trail riding. Many a time...a person enters a mud hole with the thought if I need 4x4...just turn the **** on the dash...after the fact they are stuck. Find out...a walking trip into the mud to "LOCK" the hubs...is the only way out.

Good luck...


biz

 

However, the lock status of the hubs shouldn't keep the dash light from illuminating when the **** is rotated to the 4x4 position. Else, no one who converts to manual hubs would ever know!

If this is like the other ford ESOF systems I have played with (fortunately haven't had to on any of the superduties) there is a selector plate in the motor that idicates which position it is currently (physically) in.

Two things come to mind here. Stuff just doesn't line up quite right at a stop and it doesn't get to the position to indicate it is in 4x4.
-if you turn the switch at a stop and start to move will it then indicate 4x4? I would consider this fairly normal. If you absolutely have to be moving, then I would feel it is more of a symptom of the following.

The motor has a bad spot and can't pull in the shift fork when the t-case isn't turning.

Either way, or even if it is something I haven't mentioned, it isn't a "difficult" fix. Most of the "failures" i've seen on the shift motors is because of bad brush/commutator contact; either from corrosion b/c of a bad seal, or lack of use allowing a small amount of oxidation on the commutator. I have fixed several of these on older esof systems by carefully disassembling the motor and polishing the commutator and greasing the gear drive while i'm there. It is usually very dry.

However, I think the Superduty t-case uses a side mounted selector motor. Basically it acts on the same shaft that a manual lever would turn. I have no experience with these internally but would still consider the above the most likely scenarios. Motors themselves aren't relatively expensive, in the $150 range and if there is an issue is the 99.99% probable cause. Internal t-case failures of this nature are rare, especially on this model.

 

ok so worst cse scenario what kindof work am i looking at. say the motor is bad. how much work is it for some one new to psd's. the truck is extremely nice and i like it alot. i am just worried about the 4x4. how hard is it to change the motor and say the seals that make the vaccum for the hubs

 

bump... ttt

 

To change the motor it is about a 5-10 minute job, 3-Screws and 2 plugs and it is off also very easy to get to. The axle seal are a little more involved that would probably take a saturday morning, because you need to pull the wheel bearing assemblies off. A little time consuming but not terribly hard job and seal are about $35-$40 a piece from the dealer. The T-Case motor is about $150 from NAPA as somebody said earlier. I have done both to my truck already, If you really like this truck I don't think this is a major problem.

 

sounds like when you tried 4x4 back at sales you were in gear stopped, IF that is correct itmight have enough torque load to bind transfer case up. then it wouldn't shift until you went to neutral or let it roll. to me that would mean everything is perfectly normal, worst case i wouldn't worry about it unless it cratered buy the truck if you like the rest of it