when we got some snow last week i used 4wd and had a terrible time getting it to disengage at higher speeds, normally i could disengage at any speed without much hassle just let off the gas for a few seconds.

well as most know a lot of stuff has changed on my truck since the last time 4wd was used on the road at higher speeds.

different tires
different drive shafts (front and rear)
different gears (front and rear)
more lift (superlift)

under some suspicion i am wondering if this could be my tires that are effecting this. my front tires were bought brand new and my rear tires were bought used, the rear tires are pushing close to the wear bar and the fronts are still pretty much new. could this size difference be enough to cause issues going in and out of 4wd? at higher speeds i would think the size would be more noticeable.

do finally get it to disengage i would have to slow to under 20mph and i would get a thud and it would come out of 4wd.

any thoughts/ideas would be great/helpful

 

Good question, I have no trouble in high, but mine can be a pain to get out of low.

 

ive never been in 4wd at high speeds..you can just lock it in? lol never knew that either

called something like shiftin on the fly!?!?!?

 

bingo buddy

 

yea any speed really, flip the switch let off the gas for a second or two and then your in 4wd, same to disengage flip the switch let off the gas and a few seconds later it will be out of 4wd then get back in the gas.

i did it at 95mph because one of my buddies said it couldn't be done, worked fine.

also i have ran 80~85 in 4wd high several times.

i have never really had any issues until now.

 

i have similar problems with my 4wd as well. although i have a manual transfer case now.

i dont think it would be the different wear on the tires as much as the size of the tires putting extra strain on the t-case and the front cv shafts.

 

What the hell are you going thought, puttin your truck in 4wd at 85 mph

If it sand, i would of put it in 4wd before i go that fast..

The fastest i put it in 4wd is about 25 mph before i go thought a puddle of mud..

 

just driving man, up here roads can get slick fast. i didnt say it was right doing it but i know it works.

 

Definitely need to take the pressure off.

But according to Ford, slight differences in tire size and so forth can cause large amounts of pressure on the gears of the transfer case on "hard" roads where the tires have problems slipping.

Higher traction tires, slight differences in size and inflation pressure, weight balance, etc. can all contribute to the loading of the transfer case.

Best thing to do is to take it out at lower speeds, and to pull onto a gravel or less "tractive" surface to let the wheels torque bias equalize a bit.

 

crap, had a feeling this would be the issue, looks like i better get some funds ready for two more tires before my front two wear down too much.

 

Wow, i hope i dont have any issues like this. But i usually dont go over 50 in 4x4...Usually like 40ish, and thats usually on the e-way when the roads are bad.

 

does anyone know if the faster you go with tires of different size front and rear that it would cause the bind to be worse?

this is almost $500 in tires we are talking about here! maybe i can find someone that will let me swap their tires to my truck for a test...

 

Think about it: the faster you go, the faster the rotational "difference" builds up and the more stress there is until finally something either breaks, or tires "slip" to relieve the stress.

4x4 was NOT intended for hard surface high speed driving. It's a bad, bad idea -- particularly if you have to steer much at all. That's what AWD is for. You should only shift it into 4 wheel when traction conditions are appropriate or there is an actual problem getting moving.

This is particularly true with different size tires between the front and rear! You wouldn't put two different size tires on the right and left with a limited slip would you? No, because it would burn it up. You won't burn up your transfer case, but being in 4WD with different size tires front to rear stresses your differentials, u-joints, driveshafts, transfer case, etc.

Best NOT to use 4WD on hard surfaces, period, in your case.

 

Just come over one weekend man.

 

well i was on snow covered roads, so they were slick, im prolly just going to order 2 more MTRs within the next week or so. I'm pretty sure that is what it is doing.

 

thanks mark but that is one heck of a drive for swapping tires, that is 100 in gas that could pay for new tires!!

 

I would put money on it that it is the tire size difference, get em changed soon.......

 

i pulled the shaft, so no bind right now.

 

Cool, good thinking.......

 

Yeah i was thinking you could come over x-mas break for a weekend and we could get the go cart out and do some offroading....lol

 

lol yea that would be a blast, still have snow?

 

ok this is just a thought i just had... people have problems with the electronic motor that engages the 4x4 with it not working and you follow those steps on therangerstation.com to clean it.... MAYBE it might be a good idea to pop it off and clean it over the winter brake. it *might* be the problem... just an idea..

 

Cleaning it is a good idea if you offroad anyway, lol. Whether it's yet a problem or not, opening it up, cleaning it and inspecting for common trouble spots (like the end stop plastic piece) is a good idea.

Here's a reference from http://www.explorerforum.com that is good also: http://www.explorerforum.com/forums/...d.php?t=123542

 

No lol it sucks, been raining here the past 3 days. I *HOPE* we have snow over break..lol

 

hate to say it buddy, but with everything you've done (mod-wise) and high speed engaging, could be killing the t-case motor...although it may work fine, ford recommends that you don't engage above something like 70mph...maybe even lower!