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ttrainxl · 06-08-2023, 06:31 PM

I have a ‘95 Civic EX and used to engine off coast as much as possible. I’ve only had the car for about a year and a half, and when I bought the car, the transmission shifted well. I had been getting 42-44 mpg in the summer without engine off coasting, and managed 48.75 mpg as a best score with lots of engine off coasting. After a lot of this, the transmission became harder to shift. I checked the transmission oil and it was at a good level and was clean.

A friend that used to work in a transmission shop told me that engine off coasting isn’t very good for most transmissions. When the output shaft is spinning and the engine is not running, the gears and synchros are not getting lubed by the oilers. Similarly, some vehicles being towed by an RV with their drive wheels spinning without the engine running can cause transmission problems. It’s essentially the same scenario. I think I’ve done somewhat permanent damage to my transmission by engine off coasting. I don’t do it anymore, but the damage is done. At super low speeds, it’s probably ok, but at highways speeds and especially for extended periods (coasting down an entire mountain), you’ll likely run into gearbox problems.

Maybe not all transmissions are prone to this, but your civic transmission is built just like mine, but with different ratios. I now can’t shift into reverse with a cold transmission. I have to turn around after my drive while everything is warm, or knock it into neutral and push the car back a little to roll back and make a three point turn without reverse. First gear doesn’t shift very well, and second is an issue sometimes. Third is mostly ok, and forth and fifth don’t seem to have been affected too much.

Some people here will probably tell me I’m wrong or chime in and say they’ve done it in the same cars and not had issues. My experience is that the transmission shifted well when I bought the car, and after engine off coasting at all speeds including highway speeds and down mountains sometimes, I now have problems shifting on most drives. The car is still plenty driveable, but doesn’t shift well.

06-08-2023, 06:31 PM	#10 (permalink)
ttrainxl EcoModding Lurker Join Date: Sep 2021 Location: Virginia Posts: 70 Thanks: 0 Thanked 10 Times in 9 Posts	I have a ‘95 Civic EX and used to engine off coast as much as possible. I’ve only had the car for about a year and a half, and when I bought the car, the transmission shifted well. I had been getting 42-44 mpg in the summer without engine off coasting, and managed 48.75 mpg as a best score with lots of engine off coasting. After a lot of this, the transmission became harder to shift. I checked the transmission oil and it was at a good level and was clean. A friend that used to work in a transmission shop told me that engine off coasting isn’t very good for most transmissions. When the output shaft is spinning and the engine is not running, the gears and synchros are not getting lubed by the oilers. Similarly, some vehicles being towed by an RV with their drive wheels spinning without the engine running can cause transmission problems. It’s essentially the same scenario. I think I’ve done somewhat permanent damage to my transmission by engine off coasting. I don’t do it anymore, but the damage is done. At super low speeds, it’s probably ok, but at highways speeds and especially for extended periods (coasting down an entire mountain), you’ll likely run into gearbox problems. Maybe not all transmissions are prone to this, but your civic transmission is built just like mine, but with different ratios. I now can’t shift into reverse with a cold transmission. I have to turn around after my drive while everything is warm, or knock it into neutral and push the car back a little to roll back and make a three point turn without reverse. First gear doesn’t shift very well, and second is an issue sometimes. Third is mostly ok, and forth and fifth don’t seem to have been affected too much. Some people here will probably tell me I’m wrong or chime in and say they’ve done it in the same cars and not had issues. My experience is that the transmission shifted well when I bought the car, and after engine off coasting at all speeds including highway speeds and down mountains sometimes, I now have problems shifting on most drives. The car is still plenty driveable, but doesn’t shift well.