GMC Yukon 4x4 Service Light On

ryanideus

I have a 99 GMC Yukon. recently when using 4x4 the "Service 4x4" light will turn on after swiching to 4x4 or auto 4x4. once light turns on you can not swith back to 2wd or any other drive till you turn the truck off, then restart the truck again, then you can switch the drive.

All the drives work fine 4x4, auto 4x4, and 2wd. their is no grinding, funny noises, or any indication that anything is wrong. You just can't switch between them till the truck is turned off and restarted.

My thinking is this is a switch or sending unit somewhere that is bad. does anybody out their have any ideas?

denali2001

hi i have the same problem and i went to a autoshop and they said it is the switch that isn't responding and needs to be fixed. you can probably find the on ebay like i did. i have a 2000 denali

jwyatt

Yesterday I had the same problem pop up on my 2003 Yukon, 40K miles. I took it to the dealer who reported a code B2725 Internal Transfer Case Switch on Dash. They replaced the switch to the tune of $299. Switch $111.32 and labor $168. Total time was less than one hour clock time, so go figure on the labor rate. That is why I hate to go to Koons of Manassas, VA.

While there they wanted to do a change of the transfer case's oil and the differential cases' oil to the tune of $350. Also they reccomended an air induction cleaning (pure incentive to the service writer and techs) for $150. Any wonder why GM had to have the government bail out? I am sure other manufacturers are as bad.

jwyatt

After the $350 quote on the diffs and transfer case, today I went to my local Valvoline Service Center and got it done for $238, a significant savings. They used the appropriate GM products.