Engine klacks

My 94 ranger 4.0 v-6 makes clicking noises when hualing a load at highway speeds. How do i correct this?

You might first try using a higher octane gasoline when towing. (ouch!)

If the clicking goes away while towing then what you’re hearing is pinging or pre-detonation when the engine is put under a heavier load with a lower octane fuel. And since your truck has the OBI engine management system, this probably would’t turn on the Check Engine light.

Tester

Ouch is right. The check engine light is off. The pinging happens when i come to small hills on the interstate. I have a load of sandbags for winter traction. 121,ooo miles. Thankyou

The “ouch” is more for the damage being done to the engine while this pinging, clicking, clacking, or whatever you want to call it is going on. Any way you put it, it’s preignition and it will cause severe engine damage if something is not done about it, and the cheapest solution is to try a higher grade of gasoline. If super or premium keeps the engine happy, use it. Don’t balk at the extra ten or twenty cents a gallon if it will keep your engine together. It adds up to a measly two or three dollars a tank, much cheaper than replacing the engine.

Another thing you could try is running some Sea Foam through the intake system. Preignition is often caused by carbon, and this stuff is supposed to help break that stuff up. You will probably have to feed it through a vacuum line. If you are unfamiliar with how to do this, find someone who knows how to do it because sending a liquid through the intake system can destroy an engine faster than the pinging you currently have. The Sea Foam treatment can be done safely and may even help, but done wrong the results will be catastrophic and instantaneous.

Thankyou.