Check the vacum control unit located under the battery. Hook a vacum gage to the unit and see if it will engage if not relace unit. If it does engage trace vacum lines back to source.
The actuator on the front differential may not be engaging to lock in the front axle. How can I fix it?
No. The pinion seal would be at the differential input.
on most 83s the front axle is locked by vacume. There is a vacume canister on the right hand fender well under the hood check the vacume hoses to the transfer case
It normally would have a 4wd written on the vehicle somewhere. To be sure just look under the front. If you see a differential it is 4wd. If no differential then it is not.
front differential turns all the time
The only place you would use gear oil is in the rear differential and or front differential if it is a 4+4. The differentials have a fill plug.
I'm sure one with the right tools could fabricate it to work.... But for the general, the answer would be NO. The front is a different type of gear system. It also used different axles and mounts differently.
The front axle on these trucks have a mechanical actuator that locks the front differential in. They have used vacuum, thermal and mechanical means for this. The mechanical is the most reliable. This is a common fail point on the Chevys/GMCs. It is located on the front axle next to the differential.
my 1989 Chevy 4x4 front differential wont engage any idea on how to trouble shoot the solenoid on the front pumpkin would be great
The only seals on the driveshaft itself would be on the slip yoke. You're probably thinking of the pinion seal, which is at the front of the differential, behind the input yoke to the differential.
On the top of rear differential. Some vehicles have one at each front and rear wheel. Some vehicles have one at each front wheel and one on top of rear differential. Depends on the vehicle. The year, make and model info would help.
The 2004 Toyota Avalon does not have a separate differential; instead, it features a front-wheel-drive layout with a transaxle that combines the transmission and differential into a single unit. This design is common in many front-wheel-drive vehicles, allowing for a more compact and efficient drivetrain. As a result, the Avalon does not have a traditional rear differential, which would be present in rear-wheel-drive or all-wheel-drive vehicles.