2003 Chevy Silverado Extreme Duty

Thanks Lyn, next oil change I'll have them pull the stick.

After running through that much water, I'd have all the fliuds checked.

Good Luck! Have fun.

The water will sink to the bottom of the differential and tranny. Loosen the drain plugs if they are at the lowest point, and let the water out. If the fluid is milky, change it and the tranny filter if it's automatic.

I think once the water mixes with oil, it doesn't separate out very well.

If the water did not go over the door handles and you did not create a large ripple that would have gone higher than the door handles, you should be fine.

4X4 water traversal criteria is typically - door handles and below - good to go!

_{No I didn't just make that up - that was the common phrase back in the mid 70's during my "off roadin up to your pits in mud days...........HONEST}

The gear case(s) vents are pretty good at keeping water out provided you don't go snorkeling.

Have the fluids checked for water contamination anyway just to be safe.

I used to maintain a fleet of outboard powered boats. When we had a sinker, I would put the motors carb up and pour fuel through with the spark plugs out. The recommended drill is to rinse with alcohol to get the water out, then fuel to get the alcohol out. Then back on the boat and run the hell out of it to dry out the electric parts. We usually got another year or so after that. It was salt water, and those Mercs melted like sugar.

I do not know if it is current SOP but in 1969 the US Army required us to repack all bearings after running in any water deeper than the center hub of that vehicle. Water will not only find it's way into the tranny and differential it also will seep into your U-joints and bearings as the seals on them are not designed to take much positive pressure inward. They are mostly to keep dirt and contaminants out at ambient pressure.

Rich Hurd

Good thought. Especially if you have manual hubs with a big knob on each hubcap. That's another thing to leak.

My newer 4x4 (1985) had sealed hubs.

Hot bearings literaly suck when the yare quenched in water after a drive.

Notorious for this were boat trailers that, after a drive to the launch ramp, would be submerged. Many a boat trailer has thrown a leg on the freeway after being immersed.

Universal joints are easy enough to repack in the field with a grease gun but stub axles....invest in someBearing Buddies

Older military off road vehicles had vents on all components. axles, transmission, transfer case, steering box, master cylinder, everything. All were vented to a common vent tube that ran the length of the truck. This was in turn vented to the air intake for the engine. There was a deep fordging kit available to extend the air intake and exhause to an area that was above windshield height.

Dump the fluids and be safe. You own that truck, not any of us. If there is water in a differential, it will start to pitt the bearings and gears. That damage will never go away. It will only get worse. Two years that howl from the rear end will be expensive to repair. An ounce of prevention is worth a pound of cure.

If you plan on this type of endevors, think about extending the vents used on the truck. The factory uses rubber hoses. Just make up extentions out of more hose, or get commonly available brake lines and rout the lines together and bring them up behind the cab to bed area, Use the original vent(s) and enjoy yourself.