Hi, As stated in previous threads, i had manual gearbox replaced.
Previous one had mineral oil of unknown viscosity (Very likely SAE 140 or something even thicker). New one has Motul 300 75W-90 Synthetic in it.
When i was driving with previous gearbox, car was slowing down faster when i shifted into neutral gear. Also when the car was in neutral gear while the engine running, if i was releasing the clutch pedal, rpm dropped a little, and idle became rougher.
One more thing, The car was moving forward even in Neutral gear. (I am not sure if this was happening only at cold starts or even after the gearbox was warmed up. But even when the ambient temperature was 35 C, the car was moving forward)
Now all the problems have been solved after replacing the gearbox and the oil. Car goes very well in neutral gear. (Makes me feel as if it will never stop), there is no rpm change when clutch is released, and car doesn't move forward in neutral gear.
Last but not least, Car's fuel consumption decreased also.
Before it was consuming 10L/100KM in city driving, where heavy traffic was usual. Now it is not more than 8.5L/100 KM. (The results are not based on single test. i have tested it many times and results were virtually same)
I find it hard to belive that oil viscosity can make such difference. But nothing else was changed in the car recently.
I have tested all wheels one by one, to see if there is brake drag. But there was none
Regards
Previous one had mineral oil of unknown viscosity (Very likely SAE 140 or something even thicker). New one has Motul 300 75W-90 Synthetic in it.
When i was driving with previous gearbox, car was slowing down faster when i shifted into neutral gear. Also when the car was in neutral gear while the engine running, if i was releasing the clutch pedal, rpm dropped a little, and idle became rougher.
One more thing, The car was moving forward even in Neutral gear. (I am not sure if this was happening only at cold starts or even after the gearbox was warmed up. But even when the ambient temperature was 35 C, the car was moving forward)
Now all the problems have been solved after replacing the gearbox and the oil. Car goes very well in neutral gear. (Makes me feel as if it will never stop), there is no rpm change when clutch is released, and car doesn't move forward in neutral gear.
Last but not least, Car's fuel consumption decreased also.
Before it was consuming 10L/100KM in city driving, where heavy traffic was usual. Now it is not more than 8.5L/100 KM. (The results are not based on single test. i have tested it many times and results were virtually same)
I find it hard to belive that oil viscosity can make such difference. But nothing else was changed in the car recently.
I have tested all wheels one by one, to see if there is brake drag. But there was none
Regards
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