This is hands down the biggest complaint I have with my 05 G35x. I do a lot of long distance highway driving, and the constant 4,000 rpm drone at 80mph is ridiculous, contributes to the low mpg, and is plain noisy. My 03 Accord was revving at 2500 at the same speed.

Has anyone found a workaround to this, whether via a computer chip, different tires, anything?

thanks.

 

Good question - I totally agree, but you meant that 80mp is 3000 rpm, not 4000, right?

 

3000rpm is more like 60mph.

I'm sure the car has way more than enough power to cruise around at 2100rpm on the highway at the speed limit. Why would it need better top gear acceleration when the AT is so very willing to downshift anyway?

 

The 5A cars only have 3.36 rear end gearing but the tranny gearing is very aggressive. Fuel economy is for economy cars, sorry to burst your bubble.

 

I don't really care about fuel economy but I agree that the trannie gears could be deeper up top. On my 6mt, there is not much difference in rpm's when cruising in 5th or 6th. It would make a lot more sense to have 6th gear a deep cruising gear for fuel economy.

The only work around would be to change the final gear or go with bigger wheels.

 

3000 at 60? Are you sure? Is this in auto mode, or manu-matic mode? If it's in auto mode, take it to the dealer or something; that's not ordinary(possibly never shifting to 5th?). If it's in manumatic mode, are you sure you'rein fifth? My old 04 5AT cruised at 80 at 3k in 5th, just like the 6MT does in 6th.

To reiterate, 3000 rpms, in 5th gear, in automatic, at 60pmh(making sure I get each criteria correct), is not possible with the stock tranny and gears.

 

I am on the same page as you, Trey.

My '05 5AT is at 2,000 RPM at 60 MPH, and 3,000 RPM at 80 MPH. I know that the tranny in the 'X' is no different then the one in my car...

It certainly sounds like an issue of the transmission not shifting to the correct gear (a buddy of mine had the same problem on his B6 A4).

 

I've got 3.92 gears - and my 80MPH is only 3400...shift it dude....

 

hmm...i should try 80mph tomorrow.
never really pay attentioned to rpm cuz i never go on highways (well barely)

 

Alright, thanks for the heads up. I'll give it a spin and report back. Maybe not 3000rpm exactly, but definetly up in the high 2's. Even I thought there was something wrong on that first drive home, flicked it to manual 5, and it was the same.

 

yea 80 mph is 3k im positive for that cause im always cruising at that speed

 

I have a 05 AT, at 80mph i'm at 3100 rpm in 5th gear, which seemed hyigh to me I'm use to driving V8's so getting use to cruising at 3000 rpm is tough. Is this worse for the engine in the long run. My V8's would cruise at 2000 rpm in top gear, which is less stress on the engine. My brother has a manual Nissan Altima with the 3.5 and he said he is right around 3000 rpm at 80mph, so I guess this is normal for Nissan/Infiniti.

 

These engines are not hurt by running at 3000 rpm. They could probably do it forever..........

 

After reading this thread, I thought well when I go out the next time I will check my car and see what it does. On the interstate with the car in manumatic mode I had the following result at 80mph:

4th gear - approx 3500rpms
5th gear - just over 3000rpms

Not sure that is the average but it gives you something else to compare to. Hope you figure out what's up since it sounds like something is wrong with your tranny or something.

 

Yeah that is excessive.

good luck