Help Needed four wheel drive

phipps

SDD Junior Member
Joined
Jan 22, 2015
Messages
2
Reaction score
0
Location
grand blanc ,mi
I have a 2003 xlt 7.3 and the 4x4 switch dash seems to be not working fuses are good ,defrost and all is working fine looking for help on were to start?
 

dboyw

Full Access Member
Joined
Aug 30, 2005
Messages
358
Reaction score
0
Location
Lancaster, PA
With a switch on the dash, I will guess you have the auto lock hubs. If so, most likely is you have a vacuum leak at the hubs, common problem. Quick check is to manually turn the hubs to lock. The axle is live now but not in 4x4. Go drive and switch to 4x4. This should still engage the transfer case. Do you have 4x4? If so, start looking for the vacuum leak. The hoses near the hubs are a likely culprit.
 

phipps

SDD Junior Member
Joined
Jan 22, 2015
Messages
2
Reaction score
0
Location
grand blanc ,mi
I tried locking manual hubs still nothing, when I turn switch to 4x4 the dash light dose not come on,i pulled dash out by switch and there is no power going to switch,fuses are good,i put new relay in under hood by airbox , vacuum pump is working,no problems with switching hvac?.. the light on dash works for a short time when starting , and there in nothing going on at transfer case
 
Last edited:

DaveBen

SDD Senior Member
Joined
May 31, 2005
Messages
9,620
Reaction score
81
Location
Ukiah, California
There is a shift motor in the transfer case that can go bad. If the motor is shot, no four wheel drive. I do not know how to test the motor other than putting +12v and seeing if it engages the gear for four wheel drive. You will hear it shift.

Dave
 

JLDickmon

ursus combibo
Joined
Jun 22, 2006
Messages
4,173
Reaction score
12
Location
49041
I tried locking manual hubs still nothing, when I turn switch to 4x4 the dash light dose not come on,i pulled dash out by switch and there is no power going to switch,fuses are good,i put new relay in under hood by airbox , vacuum pump is working,no problems with switching hvac?.. the light on dash works for a short time when starting , and there in nothing going on at transfer case

there are two relays under the hood, at or near the main fuseblock that control the shift motor..
 

Members online

No members online now.

Forum statistics

Threads
30,506
Messages
266,043
Members
14,622
Latest member
rhensonsr
Top