LockedFord Explorer 4wd/tire size question

Post
Derek_2433
Mud Pro
2007/10/18 14:31:05
My g/f had 2 new tires put on the rear (I think it was rear) of her Explorer (02-03 I think), and she's got some problems in the rear-end (the car not her) right now so its in the shop... The shop told her she needed to get the other two tires IMMEDIATELY as it is currently ruining the 4wd... Its got an auto 4wd feature.. but I'm certain that the button has to be pressed in order to enable that... Anyways, I know how diff size tires can ruin a 4wheelers 4wd,,, at least I've been told that.. and the philosophy makes sense..   but is this happening on her Explorer?  I would think that unless the vehicle's 4wd is enabled (button pressed) no damage is being done... can someone clear this up for me? 
Thanks,
Derek

Oh, and if this is true, can we not call the Ford dealership and complain because they didn't warn her about this happening...? 
oldtrx
Outlaw
RE: Ford Explorer 4wd/tire size question 2007/10/18 15:05:14
definately get 2 new front tires. i work at a body shop and one came in that happened to be my cousins after a wreck and it did the same thing, turns out the small difference in grip made it shift WAY hard, and could cause problems. 2 new front tires to match the rear and it was in good shape.
MONSTERQUADMANIAC
Outlaw Extremist
RE: Ford Explorer 4wd/tire size question 2007/10/18 15:28:39
All four tires need to be the same height.......
Jake450s
Moderator
RE: Ford Explorer 4wd/tire size question 2007/10/18 15:50:18
All four tires should be the same size.  This tests my memory, but I think that should select rear wheel, four wheel auto, four wheel high, and four wheel low?  If the auto-four wheel drive can be disabled (two wheel drive only position), then there is no damage being done to the four wheel drive system in any way while you're in two wheel drive.  I find it hard to fathom that anyone would willingly install two tires only on a vehicle with an "auto four wheel drive" that didn't have a full two wheel mode.

Listen to them when they tell you that you need four matched tires on the truck in order for it to live up to it's potential, and so that you (she) can have a small piece of mind in knowing that you don't have to cringe about using the four wheel drive when it is needed.

What specific problem(s) is the vehicle having?  If it's in the "rear end" being the differential, or even if "rear end" means everything behind the transfer case, be skeptical about blaming the tires too quickly.  Mismatched tires and uninformed drivers can tear a driveline into little tiny pieces in short order, however it does what it does and doesn't do what it doesn't do... 

Now, if I'm remembering wrong about the two wheel only mode availability and you can't lock out the auto engagement of the front drive, or if she's prone to throwing it into four wheel drive before the traction gets really, really bad, then maybe you should consider the matching of the tires to be a much more critical item.
Derek_2433
Mud Pro
RE: Ford Explorer 4wd/tire size question 2007/10/18 16:24:38
The bearings are shot in the rear...

To my knowledge (she's only had the vehicle for about 5 months) it does have a strictly 2-wheel drive mode... one mode, however, is in 2wd until 4wd is needed... that would be "Auto-4wd" I assume. 
This isn't an off-roading vehicle,, so the 4wd may barely if ever be used... but thats beside the pt...
Like I said, I just was curious is she is at risk right NOW when driving in 2wd...
I'll check to confirm that her explorer does drive around in strictly 2wd...  I believe the Auto-4WD button has to be pressed in order to engage anything past 2wd mode. 

RideRed4x4
Mud Master
RE: Ford Explorer 4wd/tire size question 2007/10/18 16:54:45
Yea, all four need to be the same height. The transfer case will be torched if engaging to 4wd. exp. equiped with auto 4x4. (sp)
ragtagranchers
Super Swamper
RE: Ford Explorer 4wd/tire size question 2007/10/18 17:43:52
why put 2 new tires on the rear anyway? but if you mismatch tires sizes on the front and rear its pretty much like changing the gearin around so as soon as you put it in 4 wheel drive it will start to shake and jump  becuz the front and back are trying to move at different speeds
 
but if their the same size same brand  but the front is just wore out more i dont think it would mess anything up, but if the tires the tires are different brands and the same size they could be a little different in size
Derek_2433
Mud Pro
RE: Ford Explorer 4wd/tire size question 2007/10/18 18:15:21
why put 2 new tires on the rear anyway?


Because she can't afford all four.  She had always planned on the other two in the near future.
So am I understanding correctly, as long as she's driving in rear wheel (2wd) drive all the time, she'd be ok? 
I understand how it would screw up in 4wd, same as atvs,, rears moving at diff speeds than fronts... I get that. 


ragtagranchers
Super Swamper
RE: Ford Explorer 4wd/tire size question 2007/10/18 19:10:44
well im just saying the front tires are the most important  because the are the ones doin the turing
freshmudder
Mud Maniac
RE: Ford Explorer 4wd/tire size question 2007/10/18 19:18:19
i always thought in auto 4x4's it locked in 4x4 at the front axle[&:] but im not an expert on the newer transfer cases. but i do know if your vehicle isnt geared for different size front and rear tires that it will mess up your transfer case! our samurai head 1 inch smaller tires on the front when we bought it and it was stuck in  4x4 and they had to take out the front driveshaft cause they couldnt afford new tires.
Kodiak 450
Mud Pro
RE: Ford Explorer 4wd/tire size question 2007/10/19 07:17:09
Just out of curiosity what is the difference in tire sizes?
coonhound130
Mud Monster
RE: Ford Explorer 4wd/tire size question 2007/10/19 07:21:37
On the Explorer the front end is always locked in , when you push the button it activates the axles to turn . You can harm them with diff tires even in 2 wheel drive . Now on the older trucks where you have a transfer case shifter in floor it will not harm it cause the transfer case is not engaged
coonhound130
Mud Monster
RE: Ford Explorer 4wd/tire size question 2007/10/19 07:22:39
Hope that makes sense , kinda hard for me to put it in words to explain it .