okay, my 16 year old son has been having a blast with the old truck that we put together (a 1967 Jeep pickup).... I've put a ton of hours and some money into getting her running well, I'm not done by a long stretch.. but, she is road worthy and he is driving it everyday to school and around the local hills and lots of stuff I'm sure I don't want to see (i think donuts aren't just for dunkin) after baseball practice in the field where they park... So, he has some symptoms that I'm about to dive in on and would love to hear from you car mechanic types! He is experiencing some power loss after a few minutes at highway speeds, then it surges back and then kind of goes back and forth.... occasionally during one of the dropoffs in power, the truck will actually die. He puts it in neutral, restarts the truck and it fires right up and when he puts it in drive, away he goes again. When just driving home to school and in town.. no issues. What has already been done 1) new carburetor (had it specially built as it was hard to find the OEM part, went to a guru and the truck has been running for 6 months without any of these symptoms.) 2) All new fuel lines 3) New fuel tank 4) new fuel pump 5) new fuel tank and pickup My first plan: I need to teach him how to change and lube the truck fully.. and since summer is around the corner, we're going to flush the radiator, change oil and filter, lube the chassis AND change the transmission fluid and install new screen. (I suspect his oil pickup is also not working properly, but that is a separate problem and common on the old Kaiser 327 engine) I had a similar issue with an old chevy truck I had years ago and just by changing the transmission filter/screen... the surging issue disappeared, so, it is a cheap and easy solution and a good thing to try. The tranny is a TH-400... After the fluids are fully replaced, we'll give it a test drive and see if we still have the problem. I'm kind of thinking of using the tractor version of transmission fluid on this truck... it has a tendency to tighten things up which also may be helpful. Okay, I'm open to suggestions before going to the transmission guys... and if you have suggestions for resolving the oil pickup not generating enough pickup, I'd love to hear them!