Gearbox: Difference?

The diesel will be ratio'd so that it cruises at a lower RPM at the same speed that the petrol would at a higher RPM so that the engine is at its best toque placement. For example.

Petrol engine gives out peak torque at 4000RPM and in 5th this would equate to 75MPH

Diesel engine has peak torque at about 2500Rpm and in 5th gear will cruise at 75mph at this engine speed.

If you do a lot of town driving I could see it being useful as you wouldn't have to change gear as much in traffic, but on the motorway and long A roads the engine would have to work harder, and you would no doubt have to down change to maybe 3rd to overtake on a single carriageway Aroad where as you might have been able to stay in 5th or 4th at a push.

All depends why you want to replace it and what its going to be used for.

wouldn't the differance be in the diff?

Not necessarily. Could be either or both. Mike.

"Marty" mumbled:

Out of interest...what's this? I /am/ using a fixed pitch font, but it still looks like a cross between someone sticking up one finger and a dying swan.

I suspect there's no difference. The difference in gearing would be from the Diff ratio......its cheaper to produce a different Diff than produce 2 different gearboxes.

However this is not to say that the gearbox would lift out of a diesel and slot into a petrol model......the clutch plate diameter and hence the bell housing are likely to be different.

Not so on most Renaults I have come across. Diesel box's I think are made a little stronger anyway due to the amount of torque they put out though.

But we're talking Nissan Primera here.

More Torque.....on a Nissan diesel? Look at the stats.

Nissan 2.0 Diesel - 1974cc - 75bhp - Top speed 103mph - 0-60 in 16.6 sec

Nissan 2.0 Petrol - 1998cc - 121bhp - Top speed 120mph - 0-60 in 9.4

I would suggest that putting your foot down in the Petrol version would transmit more force through the transmission than the diesel would.

Peak Torque is still probably higher, and at lower revs where it is used more.

That could be one of the anomolies, though...

Phil