Control-Trac messed?!?!

[STL_Explorer]

I have a 98 Explorer 4.0L SOHC EB. This thing has the Control Trac 4WD system which is capable of diverting up to 96% of the engine torque to either axle (i.e. the auto/4wd/4lo system or auto hub system). Recently I have been having a weird problem when I brake, it seems to sound like the front transfer case is "locked in" and the front end moans and kind of grinds. The weird part is that it really doesn't happen right away after I start driving, it progressively gets worse the longer I drive. I have a 1 hour commute from work and I really notice it a lot when I get close to home.

I tested the truck out this weekend when it was still cold and not acting up. I engaged changed the 4WD switch from "Auto" to "4wd" on dry pavement and did some test stops. I think it sounds. That's why I think the system is some how locking in my power to the front the longer I drive this thing.

Do you guys have any idea? Is one of my wheel slip sensors failing? Is the transfer case going? Or maybe the Torque On Demand Clutch? Wheel bearing? I just don't know.

I feel like I'm destroying this thing.
Any and all help appreciated!!!

 

[Doug]

My truck was doing much of the same thing, It started grinding when i was braking and then when i decellerated it would grind. I wasn't sure what it was at first so i tried isolating it. when i removed the front driveshaft the grinding went away. I ended up replacing my t-case with a Borg Warner 1354 manual shift and it's one of the best things i've done in the truck.

 

[STL_Explorer]

Ouch! I would prefer to not go to that extreme yet.

The 4wd doesn't sound "broken", it just seems like the front Torque On Demand Clutch is locking in more and more as I drive.

 

[Blee1099]

I believe there is a TSB out there regarding reprogramming the GEM to help with the Torque on Demand clutch.

 

[Doug]

I've had the t-case go in both of my explorers and i wasn't going to replace it with something that i would risk having break on me again so the 1354 was the best option for me.

 

[SWLathrop]

And in the same breath, not to say that you don't, but are all 4 tires the same make, model and size? Asking this because we had a 99 come into the shop with the same symptons. Problem was cured by putting 2 new tires on the front the same as the rear. The customer bought new snow tires for the rear and left their "SUMMER" tires on the front (A 4X4 NO-NO). All were 255/70/16's, but the winters were taller causing drive line binding after driving for a while.

 

[Mbrooks420]

or auto hub system)

Well, the good news is that you don't have auto hubs. The hubs are solid, and never lock/unlock. Like Blee1099 suggested there is a tsb out for t-case harshness. I have a damaged TOD clutch and all it does is slip.( I have 2wd,auto, and low) It never makes noise slowing down(in auto) it just slips under high torque. I would change the fluid. I have read that members here have, and it took the bugs out of their t-case. Also like Doug mentioned, these aren't the most stout t-cases, and do not like to be abused. If only used on road, and not abused it should hold up fine. If you are going to be stomping on it, I'd swap in a bw1534.

 

[Doug]

Both of my t-cases went before i had tires any bigger than 31s. I still don't trust them.

 

[Mbrooks420]

I don't blame you. My is junk, and I'm a lowly stocker.

 

[STL_Explorer]

Blee1099: Thanks for the heads up, I will look into that TSB.

SWLathrop: No there are 4 Bridgestone Dueller ATs on this thing all the same size. Different size tires will "trick" the slip sensors, which is why I think one of my sensors is going bad but is not dead yet.

Doug: When your transfer case(s) were going out, did they act like this? The 4wd system still works great in the "4wd" mode. That is why I don't think it's the transfer case itself. That being said, if the t-case is going dead will the bw1534 work with the stock components?


I don't play that hard with my explorer, it is 98% of the time a daily driver and 2% of the time a seasonal hunting vehicle. The more I think about this problem the more I want to examine what the Torque on Demand clutch is being told by the GEM and what the GEM is being told by the "slip" sensors. Is there a good ODB II software package and cable to do this?

 

[STL_Explorer]

Does anybody know what TSB number I should be looking for?

Thanks!

 

[proletariat]

My company truck has started acting up. We recently had a hurricane here, and I've been driving it around in about a foot of saltwater on a regular basis. I've been driving through the sand quite a bit. Now every time I pull out of a parking space, turn out of a road, etc. it makes the grinding/binding noise you're describing. It feels like riding on mud tires w/ large lugs at slow speed. Unlike you, it only does it when I start to go and turn at the same time.

 

[Doug]

you only get a grinding at slow speeds and when turning? it sounds like it could be wheel bearings. when the t-case went in my 96 it would make a ratcheting noise and 4wd and not go anywhere. on my 97 i would get a grinding noise when deacclerating and then finally the t-case would ratchet in 2wd and thats when i was forced to replace the t-case. you could try doing the 2wd mod and seeing if that helps at all. if it is infact your TOD clutch that mod should isolate the problem. There is one other thing you can do to test the t-case by putting it in 4wd and getting on the gas a bit, nothing crazy but my neither one of my t-cases would make a ratcheting noise till i got in the gas a bit. if you try this do it on gravel or dirt not pavement. Though if it occurs after an hours worth of driving i'd lean towards there something being wrong with electronic controls and you should try the dealer before anything else.

 

[STL_Explorer]

I set up a dealer visit for tomorrow. I can hear the cash register now. There was a recall recently for a bolt in the driver's seat, so they can do that while they are at it.

Does anybody know what TSB number covers the GEM talking to Torque on Demand clutch issues?

 

[Blee1099]

Well the TSB 97314 was for my GF's 97 X SOHC. I remember it would bind and shudder especially when turning. Not sure if this relates to your problem but it's a good place to start. I highly suggest going to www.alldata.com and doing some research. They have a database of TSB on that site.

 

[shoes]

i too think i am having some tcase problems but nothin real serious.....yet

i admit i haven't treated it very kindly on the trail and i'd like to invest in a manual, heavy duty case in the future. I have a 97 sohc auto XLT with control trac. my question is...if i get a manual case...what happens to all the electrical control-trac components, and can i even get a manual case for mine? also, if u switch to a manual case...how would i engage the front shaft? if you havent already guess, i'm sorda lazy and havent done much research but i'm hopin u guys can teach me some stuff.

thanks,
taylor

 

[Doug]

The control trac all all controled by them GEM (general equipment module if i remember correctly) and there is really nothing you have to do to disable it. since you have a 97 the front end is always turning so you dont have to worry about that. here's a thread on a guy who is doing the swap right now. http://www.explorerforum.com/forums/showthread.php?s=&threadid=89545&perpage=20&pagenumber=1

 

[Mbrooks420]

GEM=Generic Electronic Module I believe.