right i get it. so if i was in fourth going up hill i should put it in 5th now?
i used to drive round keeping the revs low for fuel comsuption but maybe thats whats done my cltch going 30 in 4th maybe not good idea
other way around - 4th should be 3rd gear but it all depends on the conditions, speed of the road, steepness of the hill etc
What works for me might not work for you but the key is not to stress the engine. Be in the right gear at the right speed for the conditions
It's basic driving 101 and is what you learn when being taught to drive (I Hope!)
30mph in 4th is perfectly fine as long as the road is flat or downhill but if you then want to accelerate I'd change down a gear or only apply a light throttle until you're doing 40mph before pinning your foot to the floor