Just for curiousity sake,what is the max rpm range and speedon 4th gear is not detrimental on our engine and also economical fuel mileage wise on flat roads? Iknow that i could go up to 4000+rpm on 4th @ 70 mph going uphill on mountain roads but i have not gone that far when on flats, Iwould have thenshifted to 5th by the time i hit 55-60 mph @3000-3500 rpm. I look at my manual and it shows max speed on 4th is like 80 mph or so(really?).that would put the rpm at about 4500/5000+, is that still safe at that gear? I guessi'm afraid to blow up my engine since it's the only car i have. and also what would be the effect on fueleconomyin regards to the rpm range? probably low... thanks for any inputs fellas,

 

The maximum speed for 4th gear is well above 100 mph, the max speed for 3rd gear is ~100 mph.

If you are driving on flat road you should be in 5th gear when cruising. Mountains, that's a different story. I guess I just don't understand why you want to be driving in 4th gear if you don't need to... I guess it depends on what you're doing. If I was on flats driving wide open throttle I would redlining every gear, for just cruising down the highway at any speed, the highest gear is always best for fuel economy.