3.55 to 2.73 rear?

fud2468 · 11-01-2009, 07:12 PM

Hi,
Am thinking of getting a '99 P71 which I assume will have a 3.55 rear.
I want economy, so would try to switch to a 2.73 if it can be done.
What would it take to do this?
Ray Mac.

theoldwizard · 11-01-2009, 09:10 PM

Simply a gear set swap.

I say "simply", but it does require a skilled, trained mechanic to do it correctly.

fud2468 · 11-02-2009, 07:01 PM

Thanks.
OK, well,what if I changed out the whole rear end instead of changing the gears.
Would it bolt up?
Ray Mac.

regal55 · 11-03-2009, 07:07 AM

Quote:

Originally Posted by fud2468

Thanks.
OK, well,what if I changed out the whole rear end instead of changing the gears.
Would it bolt up?
Ray Mac.

yes and much less opportunity for something to go wrong, I am considering the same swap.

I wonder what mpg increase to expect.

theoldwizard · 11-03-2009, 07:12 PM

Quote:

Originally Posted by regal55

I wonder what mpg increase to expect.

2-3 mpg on the highway, maybe 1 in the city.

fud2468 · 11-03-2009, 09:13 PM

The EPA site says 16 mpg city and 22 highway for the '99 base CV, 14 and 20 for the PI.
Checking on Edmunds.com and other sites, up to 26-27 mpg highway for the PI and up to 30 for the base CV is reported. Of course that's doing no more than 60-65, level road, steady speed, etc. which most PI owners would probably not want to do, or care to do.

Ray Mac