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Knocking noise when deccelerating

I was driving my 1988 Chrysler LeBaron on the freeway today and after about 35 minutes of driving my car starting making a knocking noise when I took my foot off the gas pedal. If I accelerated or braked the noise would go away, but the second I was coasting the knocking would start again. I naturally pulled off the road IMMEDIATELY and killed the engine. I examined under the hood for anything out of the ordinary, but I know little about cars and didn’t see anything obviously wrong. I did notice that I was leaking a little bit of transmission fluid and was able to pinpoint the source of the leak to a hole in the hose connecting the transmission to the radiator. I will obviously be replacing the faulty hose, but can leaking transmission fluid be the reason for the knocking noise, or is something else potentially wrong?

Have your vehicle front end checked out. The motor mounts on this vehicle are suspect as well as the CV joints. They often knock under decceleration as it puts a load on the component.