Transmission slipping, cannot go over 30mph. Sometimes RPMs will surge, then drop down surge again and will repeat this process. Visible check underneath shows no leaks. Fluid checked hot, red, clean but appeared to be way overfilled. Had truck 3 years no problems. 2006 Silverado 4X4

SOURCE: 1990 Accord - Leak under car (while idle - drips)

I had a similar situation a few years ago. I was the heater hose leaking Preston which was somewhat diluted. It too was sweet...it's poisonous, so stop tasting it. Here's how you can check a difficult leak. Take the cap off the radiator while it's running, if the leak speeds up then it's a water leak from one of your water lines to the heater which is located near the firewall. Leaks do travel. Good luck and hopefully this solves your problem, I remember how it baffled me.

SOURCE: 89 ford F150 4x4 302 stalls on exceleration.

There are a couple of things you can check. Ford used two fuel filters on some vehicles, but you don't see much information about the one mount on the frame because they expect it to last for the life of the vehicle. The one of coarse is on the firewall and you probably changed that.
To find out if you have the second filter and it's more likely that you do than don't.
Look along the inside of the frame between your high pressure pump and the fuel tank[mine is where the skid plate that protects the transmission is located and I have to drop the skid plate to reach it] see if the fuel lines run into a round looking plastic box that is mounted behind a metal shield, if you see it you will need to remove the shield to reach it. It's necessary to unscew the canister and replace the cartridge which most auto parts stores carry.I found it easier to work on if I remove the fuel lines then took the filter unit out, but you may not have to.
Another thing you can check is the fuel pressure regulator. Especially if you have the vacuum type regulator, because the diaphram can develop a pin hole that leaks raw fuel into the intake manifold and cause alot of squirrelly problems. The leak can eventually become bad enough to fill the cylinders with raw fuel and lock up the engine because unlike air liquid can not be compressed.

SOURCE: 98 dodge ram 1500 5.9L 4X4 transmission slipping

your transmission runs through part of the radiator. Check your fluid level and see if your hoses are conneced right.

SOURCE: After transmission leak I need to add oil to 2001 Lincoln LS V8

look for the red dip stick its usually in the back area ,,the best way to fix that is to use a quart of lukes transmission slip and sealer it is the best on the market and coast about 11 dollars that's a way to start first ...good luck hope this will help

SOURCE: I have a 4x4 chevy silverado truck and just had a new motor insta

The factory specs for the Transmision Shifting Positioner would be different TSP adjustment should need to be tighter in Looser out I know it seems backwards but that is how it works. If I am hauling I bring it in and vise versa I believe 99 have a TSP Cable. on the throttle body.if not your transmission kit might have a problem.