Q: Truck makes grinding noise when 4WD is engaged and put under load only.

asked by on July 16, 2017

If truck is in 4WD and going in a straight line on a dirt road, little to no grinding is heard. If truck is in 4WD (4Hi or 4Lo) and in mud, truck makes loud grinding/clacking sound when throttle is applied (straight or turning). Checked front diff, looks brand new and has new oil in it, T-Case has new oil but has never been serviced. U joints are all spicer non greaseable joints and seem to spin fine. Have not checked u joints at front axles or cv joints.

My car has 215000 miles.
My car has an automatic transmission.

Grinding sound from transmission Inspection $94.99 - $114.99 Get a Quote

Hello, thank you for writing in. Issues like this can be difficult to locate, because you need the vehicle to be under a similar load to recreate the noise. With that being said, you may have a vacuum issue causing the gears to grind when changing to 4x4. Servicing the transfer case should be done with 215,000 miles on the vehicle. Do this anyway, regardless if it solves the noise. If this issue is not resolved with the transfer case or a vacuum leak, there is a strong possibility your transmission is to blame. For more help with diagnostics, contact our service department to schedule an appointment.

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