Hello,

I've done my best to search but maybe there are some gurus who could assist. I'm a newbie to the world of trucks, and am slowly teaching myself about them bit by bit, with the help of Motortrend and this forum.

Ive got a 75 F150 "Ranger" with a 360 motor, C6 tranny. Recently rebuilt 2bbl motorcraft carb, new air cleaner, all related carb and cleaner gaskets, new distributor, freshly timed(to the best of my ability) new alternator, refurbished valve covers, new gaskets, etc.

Now the problem - The transmission recently, when warm, would automatically kick down from third to second when I let off the gas. Now today, it wouldn't even shift past second, which makes highway travel near impossible.

It was a hot day, and I was driving about 35 on the highway just trying to get back home, when I could hear gurgling/squirting noises coming from the engine compartment. I thought maybe motor is overheating, and its squirting coolant, or maybe oil out of somewhere. Gauge was reading okay (though I've heard you can't trust them) and when I got home the motor would not make the sounds idling in the driveway.

My suspicion is, tranny not wanting to shift past second = motor working harder = motor overheating or getting close to it. Now why the tranny is doing this, I'm not sure.

I did replace the coolant temp sensor, but have not even located or looked at the thermostat.

Once again, kind of new to this, so I'd really appreciate any insight I can get.

 

Maybe the transmission is overheating? Check the fluid first Make sure fluid is passing through your transmission cooler. Check the vacuum line going to the transmission and the vacuum modulator.

 

Vacuum line on the transmission line seems okay. Where does it come up on the engine side?

Have yet to check the lines and see there is fluid. Thanks for the patience.