4x4 NOT Working!!! Need help Fast!!
Posting Guru
Joined: Sep 2003
Posts: 2,259
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From: Florida Hill Country
Steve83,
Thanks for the info! For some reason the service department didn't inform me of that, I wonder if they knew? They WILL now! The first hubs were replaced under warranty. The manual Warns were not.
Service Department
Thanks for the info! For some reason the service department didn't inform me of that, I wonder if they knew? They WILL now! The first hubs were replaced under warranty. The manual Warns were not.
Service Department
Post Fiend
Joined: Nov 2002
Posts: 9,987
Likes: 7
From: Memphis, TN
Here's an excerpt from the '96 service CD:
Buzzing and ratcheting noises were a constant concern with older 4x4 vehicles. These noises occurred usually when shifting into 4-wheel drive after starting a vehicle that had been sitting cold for several hours. The noises would also occur just after shifting from 4-wheel drive to 2-wheel drive. Cold weather was another factor that produced the noise concerns. Colder temperatures increased the viscosity of the axle lubricant, resulting in a much higher torque requirement for the transfer case clutch that could only rotate the pinion gears enough to cause the hubs to partially lock, which resulted in a ratcheting noise.
The newer vehicles, however, utilize a 75W axle lubricant with low viscosity and a transfer case clutch with a higher output. Both innovations allow for 4x4 operation in extreme temperature conditions.
Noise concerns in 2-wheel drive, just after shifting from 4-wheel drive, can occur if one of the hublocks fails to disengage. As the vehicle moves forward, the one hublock that has failed to disengage will rotate its axle shaft through the differential and attempt to rotate the other axle shaft in the opposite direction. As the opposite shaft turns in the reverse direction, the hublock will attempt to engage (sometimes referred to as differential motoring torque), which will result in a ratcheting or buzzing noise.
This type of noise concern is usually found on axles that have very few 4x4 miles on them. As the front axle accumulates a minimum of 250 miles of locked hub operation, the axle will break in, which reduces the amount of differential motoring torque significantly. To accomplish this, engage 4-wheel drive and then shift out of it without disengaging the hubs. This will break in the axle. Should the vehicle be put in reverse gear during this time period, the hubs will disengage and will have to be locked again by repeating the engagement procedure.
I was mistaken earlier when I wrote "~50 miles". I've edited it.
Buzzing and ratcheting noises were a constant concern with older 4x4 vehicles. These noises occurred usually when shifting into 4-wheel drive after starting a vehicle that had been sitting cold for several hours. The noises would also occur just after shifting from 4-wheel drive to 2-wheel drive. Cold weather was another factor that produced the noise concerns. Colder temperatures increased the viscosity of the axle lubricant, resulting in a much higher torque requirement for the transfer case clutch that could only rotate the pinion gears enough to cause the hubs to partially lock, which resulted in a ratcheting noise.
The newer vehicles, however, utilize a 75W axle lubricant with low viscosity and a transfer case clutch with a higher output. Both innovations allow for 4x4 operation in extreme temperature conditions.
Noise concerns in 2-wheel drive, just after shifting from 4-wheel drive, can occur if one of the hublocks fails to disengage. As the vehicle moves forward, the one hublock that has failed to disengage will rotate its axle shaft through the differential and attempt to rotate the other axle shaft in the opposite direction. As the opposite shaft turns in the reverse direction, the hublock will attempt to engage (sometimes referred to as differential motoring torque), which will result in a ratcheting or buzzing noise.
This type of noise concern is usually found on axles that have very few 4x4 miles on them. As the front axle accumulates a minimum of 250 miles of locked hub operation, the axle will break in, which reduces the amount of differential motoring torque significantly. To accomplish this, engage 4-wheel drive and then shift out of it without disengaging the hubs. This will break in the axle. Should the vehicle be put in reverse gear during this time period, the hubs will disengage and will have to be locked again by repeating the engagement procedure.
I was mistaken earlier when I wrote "~50 miles". I've edited it.
Last edited by steve83; Nov 25, 2003 at 09:02 PM.
Posting Guru
Joined: Sep 2003
Posts: 2,259
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From: Florida Hill Country
Originally posted by 3broncocrazy
HEY - Did i hear my name used in vein here..........rlh, i'm gonna keep my eye on you
HEY - Did i hear my name used in vein here..........rlh, i'm gonna keep my eye on you
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