The bearings are more likely to need service then the diffs. As you drive, the bearings heat up, cold water makes them contract, as well as the lube in them. The fast contraction of the lube can draw whatever is touching the seal through the seal, in this case water. Most diffs have vent tubes off the top of them to the bottom of the trucks body, if yours don't I would get some vacuum tube and make some.
If you are going to make a habit of playing in the water, your should extend vents off both diffs, the transfercase, and the tranny up to the top of the firewall under the hood.
Another issue is if you have been driving for a bit that heated up the fluids
and their cavities...the instant cold can draw in water...some times past seals
Watching folks is not a good indicator either...maybe they have no problems...maybe
they do, but won't know about it till they either have damage or open it up to
Normal truck tire is around 30" in dia, which means about 15" or less to the
center line, which means that some part of the diff is touching the water
If running 'fast' enough through that water, it will or may create a wave that
will be deeper than 15"...
OBTW...folks in engineering are paid to be worry warts...or anal about things
(which is really detailed and thorough)...think about it when you get on a plane
or some such that has very low safety margins by design...do you want the guy
who is lax or careless or NOT detailed designing whatever is holding that plane
up in the air?
-Ben Picture of my rig
1996 GMC SLT Suburban 3/4 ton K3500/7.4L/4:1/+150Kmiles orig owner...
1980 Chevy Silverado C10/long bed/"BUILT" 5.7L/3:73/1 ton helper springs/+329Kmiles, bought it from dad...
1998 Mazda B2500 (1/2 ton) pickup, 2nd owner...
Praise Dyno Brake equiped and all have "nose bleed" braking!
Previous trucks/offroaders: 40's Jeep restored in mid 60's / 69 DuneBuggy (approx +1K lb: VW pan/200hpCorvair: eng, cam, dual carb'w velocity stacks'n 18" runners, 4spd transaxle) made myself from ground up / 1970 Toyota FJ40 / 1973 K5 Blazer (2dr Tahoe, 1 ton axles front/rear, +255K miles when sold it)...
Sold the boat (looking for another): Trophy with twin 150's...
51 cylinders in household, what's yours?...
As an avid boater, and off road enthusiast I learned long ago that bearing buddies are your friend on the trailer, and snorkles on the diff, transfer case, and transmission will save you a lot of trouble. The last three 4X4 vehicles I've purchased came from the factory with snorkled. Not sure if it was part of the skid plate/protection package or if they just do it.
How much water you may have gotten into the things varies greatly. If you had been running hard and heated up the diffs, transmission etc then got in the water, the cooling effect tends to make it suck water in more than if things hadn't been heated up prior to getting into the water. How much if any damage the water may cause is kind of unknown. I've drained differentials that appeared to be half water before, and as far as I could determine, they didn't have any excessive wear, just a lot of sludge type goo to clean out.
Most have them, a very small hose, usually 1/4" OD or a bit bigger. Normally not that long either, like 2-3". Reality is, could be as good as a hole in the diff from where they are at. For most of us, not a big deal driving thru puddles etc. If you cross rivers/streams etc that are 100+ yds a lot......now time to do something. A reasonably quick in and out.....should not be an issue.
05 Chev CC D/A LS Dooley
92 Navistar dump truck, 7.3L 7 sp, 4.33 gears with a Detroit no spin
00 Chev C2500, V5700, 4L80E, 4.10, base truck, no options!
92 Red-e-haul 12K equipment trailer
3 Single axle utility trailers
Due to flash flooding last night, I was forced to drive down streets and roads with over one foot of water on them. I wonder if there is any risk of damage to a 2 wd Silverado pickup and what should be checked? I got home with nothing more than delays and everything is operating normally.
I personally wouldn't worry. I had a similar experience in my Mother's 2000 Mercury Mountaineer when it had <2,000 miles on it. 12 years and 140,000 miles later, it's just fine, and the fluids weren't changed afterwards.
02 Ford Explorer 4.6 V8 4x4, prodigy and equalizer
07 Crossroads Sunset Trail ST19CK
and no payments