So I was being stupid one night, driving a little too fast on slippery grassy road, and as I went around a turn my truck decided to go straight and I ended up in the lake up to my windshield. I put my truck in 4 wheel drive and reversed almost all the way out of the lake, then my buddy pulled me out the rest of the way.

The truck runs fine at idle, and when I just drive it without any strain. But I took it out on the highway and the throttle started jumping when I started to go up a hill or accelerate at a moderate pace. There is also something fishy going on during this throttle jumping that jerks the truck.

I checked the air filter later and there were light mud stains in the bottom of the plastic housing but the top of the air filter was clean (everything dry now). I am due for an oil change, so will definitely do that ASAP.

Anything you recommend I also do? Thanks!

2002 Chevrolet Silverado Z-71 5.3L Vortec V8

 

Check all the fluids and be sure none are a milky color, even the trans fluid. Its also possible that something on the engine may have cracked when the hot engine met the cool water, but I doubt that.

 

Checked the fluids and they look somewhat clean - will probably change them all out anyway. Thanks for the help nauticstar

 

check the spark plugs. the gas tank may have also got water in it.

 

I figured it out - it is actually a transmission problem rather than an engine problem. The tranny fluid is way too high, so I think water may have seeped into the system. I will drain the fluid and replace the filter ASAP and post the results. Thanks for the help!

 

Take it to a shop where they can flush all the old fluid out and replace it with new. If you don't you'll be leaving several quarts of contaminated fluid in the trans.

 

Took it to a shop and they opened up the filter - chunks of metal were in it. The bottom of the pan was covered with clutch material and brass filings. They took the tranny apart and rebuilt the whole thing - 2200 bucks. I think I'm gonna sell it to pay for the rebuild. Anyone want a 2002 Z71??? It drives like a new truck now - the tranny was shaky before the water exposure but now is much better. They beefed it up with "beast" components.

 

sure ill buy a truck thats been submerged in water :P

 

Haha you didn't know Z-71s increase in value once they learn to swim???

 

ha ill have to try that with mine.