4X4 Not Engaging, Vacuum?, 98 5.4
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Joined: Jan 2006
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2001 F150 4x4 does not engage
Originally Posted by GIJoeCam
From your original post:
I was assuming you had the electronic shifter because of these statements.
It can't be the transfer case shift motor because (if you have the floor shift) you don't have a motor.
Once again, shift into 4wd and see if the front driveshaft locks to the transfer case. If it does, we'll look more closely at the front axle. If not, you've clearly got a transfer case issue.
GEM stands for General Electronics Module. Basically it's the brain that controls all the accessory functions, essentially everything electronic except the engine and transmission.
If I was going to guess, I'd guess it was the feedback to the GEM from teh t-case. The GEM isn't finding out that the t-case is engaged and, therefore, isn't locking the front axle. Again, without a diagnostic system to tell us what the GEM is seeing from the t-case, there's no way to know exactly where the problem is.
Start with the front driveshaft check.
-Joe
I was assuming you had the electronic shifter because of these statements.
It can't be the transfer case shift motor because (if you have the floor shift) you don't have a motor.
Once again, shift into 4wd and see if the front driveshaft locks to the transfer case. If it does, we'll look more closely at the front axle. If not, you've clearly got a transfer case issue.
GEM stands for General Electronics Module. Basically it's the brain that controls all the accessory functions, essentially everything electronic except the engine and transmission.
If I was going to guess, I'd guess it was the feedback to the GEM from teh t-case. The GEM isn't finding out that the t-case is engaged and, therefore, isn't locking the front axle. Again, without a diagnostic system to tell us what the GEM is seeing from the t-case, there's no way to know exactly where the problem is.
Start with the front driveshaft check.
-Joe
Technical Article Contributor
Joined: Dec 1997
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From: Windsor,Ontario,Canada
The first thing to test is all the fuses and then the front axle engagement. Jack up the front wheels and shift it into 4x4. Try turning the front drive shaft.
If it doesn't turn it is the front axle that doesn't engage. If it does it is a t-case issue.
JMC
If it doesn't turn it is the front axle that doesn't engage. If it does it is a t-case issue.
JMC
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Joined: Jan 2006
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No manual
Originally Posted by JMC
The first thing to test is all the fuses and then the front axle engagement. Jack up the front wheels and shift it into 4x4. Try turning the front drive shaft.
If it doesn't turn it is the front axle that doesn't engage. If it does it is a t-case issue.
JMC
If it doesn't turn it is the front axle that doesn't engage. If it does it is a t-case issue.
JMC
Technical Article Contributor
Joined: Dec 1997
Posts: 9,417
Likes: 11
From: Windsor,Ontario,Canada
Member
Joined: Jul 2005
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4x4 mode
have you tried checking the actuator rod that connects the vacuum switch to the transfer case?? If you don't use 4x4 that much that rod can get gummed upor rusty and not engauge, or be intermittent. It is easy to test clean, and lub with a light oil
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Manual download
Originally Posted by JMC
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Joined: Jan 2006
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Found the prob
Originally Posted by richard zapata
Thanks, exactly what I was searching for
