Axle ratio ???

tjosh

Been looking at pickups lately (mainly the Ranger
& the Dakota), & I've noticed that you can get
different axle ratios. My understanding is that a
higher number means more torque (& thus, better
acceleration, & better take-off when towing), while
a lower number means less engine wear & better
mileage. Is that right? Also, is it worth the
extra money to get an axle ratio that is different
from whatever comes stock?

quadrunner500

In a nutshell, that is about right, but the difference is no more than 10%, maybe not at all if you are towing or toting heavy loads regularly. Are you sure about it being extra money? Not on the Silverado.

tjosh

On the Dakota, it may not cost any extra. I haven't checked yet. On the Ranger, I noticed that the 4x4 Off-Road package comes with an increased axle ratio (4.10 vs. 3.73) for ~$375
more. You can also get a 3.55 ratio, but I don't
know yet if that costs extra. I probably spoke
too soon when I said it would cost more. Thanks!

cookie1

I own an 96 S-10 with V6 and automatic. On this truck I went with an upgrade to a 3.42 vs. a 3.08 rear axle ratio at no charge. What I would suggest is to go with no more than a 3.73 or Ford or Dodge equivalent of that axle ratio, hopefully at no charge for upgrading, unless you are constantly pulling heavy loads. It's nice to have the beefed up axle ratio, but do not go overboard. On the full size Chevys for 1999, on the 1/2 tons Ext. Cabs you can even order a 4.10 rear axle ratio at no charge, but I know the gas mileage would suffer by about 5 m.p.g. from about 16 to 11 from a 3.73 to a 4.10 ratio - not worth it unless you are constantly pull heavy loads.

markbuck

I went with the 4:10 on my new 1500 silverado (soon to be here). I seriously doubt fuel economy wi11 drop by 30+% with a 10% axle change. I suspect more like 5 to 10 percent. Will let you know in a couple of weeks......

quadrunner500

markbuck:
You are right on the money, 5-10% decrease on the highway if you are traveling light, but maybe not at all worse if you are towing, hauling, or driving in-town.

woj1

I too ordered 4.10 on my Silverado...mainly because my 95 K2500 Ext Cab SB has 3.73 and I end up never using 5th gear unless I am doing at least 65 MPH. The transmission ratios have to be figured into all calculations.

pharmasea

I have the 410 on my new silverado. I wanted the 373 but the truck was on the lot and it was everything else I wanted. I WAS concerned about the gas mileage but not anymore. I have been getting anywhere from 13.7 to 16.1 mpg. 13.7 was first tank and 16.1 was mix of highway and city (with rush hour traffic, and pulling boat one to and from ramp, 6000lb boat).

I am quit happy with the 410, since this is better mileage than my 94 Z71 and much more power and effortless towing.

Jim

wynn26

I have a 4.11 in my '89 Ford F-250. It is excellent for pulling and acceleration, but coupled with a 7.3 L V8 diesel, the 4.11 in the rear end provides no top-end speed. It tops out at about 90. If you want faster take-off but lower top-end speed, then get a higher axle-ratio. If you prefer a high top-end speed, but a slower take off, get a lower axle ratio.

quadrunner500

The Silverado will pull it's top end easily with either axle, because speed is electronically governed at 98 mph. This would occur at about 3100 engine rpm...piece of cake. The 4.10 is only 10% steeper than the 3.73 anyway.

Rich

wynn26,
I don't know how many RPM you're turning at 90 MPH but I wouldn't worry. In my '92 7.3L the top end was in the 97-98 range. In my '99 7.3L the top end is 91 MPH. It's all done by that f^&$@#* computer. Ford thinks that we shouldn't be keeping up with the LA-Vegas traffic ;-)
Rich

cookie1

Heck, if I would've know the 4.10 axle ratio only dropped gas mileage 5-10% on the 99 Silverados, I would have upgraded my Z71 from 3.73 to 4.10 for some real haulin at no extra charge! Even my 3.73 5.3L motor chews up and spits out the concrete while averaging almost 16 m.p.g. It is rated at 15 city/18 hwy, but even
with the 90 percent hwy driving I do, I like having a lead foot once in a while. Although, maybe with the 4.10 from a dead stop, my gas mileage might suffer considerably more than the 3.73. I am going off of what previous 4.10 buyers told me they got for m.p.g. on their previous Chevys. 15-16 m.p.g with either the 3.73 or 4.10 is good. I know when I went from the 3.42 to 3.73, my gas mileage did not suffer one bit and I had much more off the line pick up.

bigfur1

any way to tell what axel i have in my 97 Dodge ram 2500?

quadrunner500

What size tires do you have, and what engine rpm at 60 mph, and is it an auto or manual? Otherwise, you could probably call vin number to dealer and have him tell you. Sometimes, it's marked on the differential itself.

bigfur1

I could probably tell you all the info except for the speed at sixty. I bought a salvage that i have to fix up. Its an auto with 33X11.5 inch tires. I know this does you absolutly no good at all, but there it is

quadrunner500

You can pop the cover. Then count the number of teeth on the ring gear, and divide by the number of teeth on the pinion to get the ratio.

bigfur1

I already have to put a new front end on and straight the cab extentoin and the box side. I don't have the time or energy to pop of the the cover, THEN do math on top of it:)

stanford

Well, that's the only way to know for sure. Its not that big a deal to do.