Opinions on Rear Gear Ratio

[24601]

2000 Crown Victoria Police Interceptor

Vehicle Weight
3983 lbs

Factory engine specifications
HP: 215hp @ 4,500RPM
TQ: 285 lb.-ft. @ 3,000RPM

Transmission Gear Ratios
1st: 2.84:1
2nd: 1.55:1
3rd: 1.00:1
4th: 0.70 :1
Rev: 2.23 :1

Rear-end Gear Ratio
3.55:1

I drive approximately 80% HWY. Would it be worth my while to swap out the rear ring and pinion? My goal cruising speed is 60 MPH.

[Daox]

How much would it cost you in parts? You would see an MPG increase.

[24601]

3.08 and lower (numerically higher) is $180 for the ring and pinion.

2.73 is $257 for the ring and pinion.

[Daox]

I wouldn't pay that much. Keep an eye out for a deal to come along. You never know, buy a car for near scrap, take the parts you want, then scrap it yourself or something.

[24601]

My basic rule of thumb is will it pay for itself in 2 years time. It isn't a hard and fast rule, but more of a goal.

I'm average about 72 miles a day with a fuel cost of $0.168 per mile.

[ksa8907]

Keep an eye on junk yards and peiple who just want to unload extra stuff laying around. Fyi, my v6 turns 1600 rpm at 60 and the car weighs about the same.

[BabyDiesel]

My personal opinion would be 3.08 gears. In a truck with a V8, 1634 rpm would be close to lugging... however, your Vic has a much lower Cd and drivetrain loses, you should be fine cruising around with that engine speed.

I would go 2.73 only if you are planning to do aero mods that would help it roll down the road easier.

As the others said, try to find either a complete axle or scrap car. You'll recoup your loses quicker

[ksa8907]

Originally Posted by BabyDiesel

My personal opinion would be 3.08 gears. In a truck with a V8, 1634 rpm would be close to lugging... however, your Vic has a much lower Cd and drivetrain loses, you should be fine cruising around with that engine speed.

I would go 2.73 only if you are planning to do aero mods that would help it roll down the road easier.

As the others said, try to find either a complete axle or scrap car. You'll recoup your loses quicker

Im going to agree. With 2.73's 50mph would be essentially impossible in top gear.

[spacemanspif]

X3 that the 2.73 gears would be too tall. Get instruments first to see what you are getting at what rpm. I know 50mph at x-rpm is different than 60mph at same rpm but it might give you an indication of where the mpg drops off from the engine running too low...

[Baltothewolf]

Guys my '91 5.0 has 2.73 and it cruises at 50 in 4th just fine? I don't drive it carefully so I can't vouch for MPG's, but yea. Was just tossing that out there.