Tread Depth Causing 4WD to Engage?

[RescueALab]

2004 Explorer is in the shop now. 4WD light comes on and when the steering wheel is turned the truck feels like it will not make the turn as if a wheel is going to fall off. Mechanic called and ONE tire has a better tread depth than the other three which is the reason the 4WD light is coming on. He said truck is engaging itself into 4WD and I have to get 4 NEW tires - although all of the tires are in good shape. The newer tire is about 6 months old as I had a nail in the old one. When it was installed the tire depths were checked and looked good. Can this be true? I have to buy four new tires bc of one newer tire? Getting used ones means the same thing could happen!!

How does this make any sense? So every person who gets ONE damaged tire has to replace all 4 every time? I am infuriated and I dont have any money for 4 new tires!

 

[Ronin8002]

He is correct about what is causing it, but you don't need to replace all 4 tires to make the vehicle driveable. You can simply disable the auto 4WD, either by pulling the appropriate fuses or doing the "Brown Wire Mod."

See this thread for info: http://www.explorerforum.com/forums/showthread.php?t=194875&highlight=brown+wire+mod

2004 Explorer is in the shop now. 4WD light comes on and when the steering wheel is turned the truck feels like it will not make the turn as if a wheel is going to fall off. Mechanic called and ONE tire has a better tread depth than the other three which is the reason the 4WD light is coming on. He said truck is engaging itself into 4WD and I have to get 4 NEW tires - although all of the tires are in good shape. The newer tire is about 6 months old as I had a nail in the old one. When it was installed the tire depths were checked and looked good. Can this be true? I have to buy four new tires bc of one newer tire? Getting used ones means the same thing could happen!!

How does this make any sense? So every person who gets ONE damaged tire has to replace all 4 every time? I am infuriated and I dont have any money for 4 new tires!

 

[RescueALab]

Your post has helped but I'm still not sure what to ask for from the shop - I want to be able to turn on 4WD and since the tires are all the same size make and model I dont want to have to get new tires. To the naked eye the tread depth is not even apparent so I'm not that concerned about other problems, it is really as if one tire did not wear as much as the other 3. I asked him to move the tire with the most tread to the rear but he indicates the sensor reads all 4 tires. I've not read the rules for this site but if aloowed and you want to email me it would be faster, as I should get it back today rescuealab at msn.com. Thanks

 

[Bobmbx]

Your post has helped but I'm still not sure what to ask for from the shop - I want to be able to turn on 4WD and since the tires are all the same size make and model I dont want to have to get new tires. To the naked eye the tread depth is not even apparent so I'm not that concerned about other problems, it is really as if one tire did not wear as much as the other 3. I asked him to move the tire with the most tread to the rear but he indicates the sensor reads all 4 tires. I've not read the rules for this site but if aloowed and you want to email me it would be faster, as I should get it back today rescuealab at msn.com. Thanks

Your best bet is to do what Ronin advised, and pull the fuse for Auto. This doesn't hurt anything, and if you want or need 4wd, just pop the fuse back in.

Tell the shop "thanks, let me think about it".

But the shop is correct. Unless all 4 tires are the same circumference, the 4WD system will kick in when you need it the least. That can damage your truck.

 

[CDW6212R]

The other posts are correct.

The rear only has one ABS sensor, thus the back is used as an average for the rear two tires. It should be less sensitive to one back tire being a different diameter, versus one odd front tire.

Place the odd sized tire on the right rear, hoping it will wear faster than the others. Keep very close attention to tire pressures. Put a little more air in the more worn front tires, to help with edge wear and to make them "look" taller to the ABS sensors. Regards,