Hello!

I recently purchased a 08 ram 1500 SXT 5.7HEMI quad cab 4x4 with a 6.4 bed.

Living in Toronto Canada and used the 4x4 for the second time yesterday since buying(nov2020) the truck. Just this morning noticed a weird grinding sound. I have recently changed the rear pads, rotors, shoes, backing plates, axle seals and rear diff pinion seal with new diff fluid(roughly 2-3 weeks ago). Truck ran great til yesterday after using 4x4. When I give gas there is no noise at all. When I let off the gas and let the truck roll around 20-40km that’s when I hear the grinding noise.

Unfortunately working out of town with -20 weather and not trying to go under the truck with slush and snow.

Any ideas or suggestions to what this issue could be?

 

My first thought is the joints on the front drive shaft. How many kilometres on the truck?

 

205,000km

 

I'm old and not metric but that equates to about 120,000 to 130,000 miles. I would check the universal joints on your front drive shaft. They may have gotten stiff from rust and lack of use. I've seen the bearing on front shafts grind the ball bearings to rust. If you have a splined shaft, I'd check the splines too.

 

the rear pinion nut ended up coming loose somehow! Luckily no damage was done to diff. Replaced the diff fluid and torqued the pinion nut to 210ft/lbs. problem solved!