I have no clue what the problem is here. When I accelerate and usually I have to accelerate hard enough for it to downshift, I can hear the tranny fluid. It sounds like water running through a hose or something. I have had a whole string of strange tranny problems so I'm not shocked but I don't know what to do with this one.

I had to put a new vacuum switch on the transfer case and then I had the 1870 code so I just replaced the valve body with a new one.

Any suggestions on the fluid sounds would be great.

Thanks.

That sound is not tranny fluid, it is air in your heater core.

Replace your rad cap with a Stant and DON'T install another AC Delco.

Is yours a 1997?

Blazer, It's a 1998. Thanks for the info! I'll check on that tomorrow.

When the engine is cold in the morning, remove the rad cap and look to see if the coolant is right up to the top.

replace the rad cap, fill the overflow tank half full with mixed dexcool and go for a drive with the windows down and the heat on max.

This will get the air moving and out of the heater core.

Does it matter if I get the regular cap or the vented one? The old one was pretty crusty on the underside when I took it off. I cleaned it up and put it back on. I'll get a new one today.

Thanks for the info.

Get the standard non-vented cap.

Same problem here. It was about to drive me nuts until I figured out what it was and then I was like oh no big deal. It will work its way out. Good to know that a replacement cap will fix the problem for good. Thanks for the advice.