Determining Rear Axle Ratio

[rebel_horseman]

I'm going to look at a truck this evening and I need to figure out how to determine the rear end ratio. If I remember right, these trucks came with a 4.10 and 3.73 (or was it still 3.55s in these trucks?) How can I tell which? The truck is a '97 F350 S'cab DRW 2wd. It's supposed to be a PSD with the E4OD and under 110k miles. Don't know anything more than that. Anything about these model years that I need to know about and look for?

TIA,

B

 

[hheynow]

Driver's side sticker in door jamb. Look at the bottom line for the axle code.

http://www.drivetrain.com/Fordtrkratio_posidata.html

 

[tonkadoctor]

There should be a tag on the back of the axle or differential cover that will tell you what the gear ratio is.

There should be an axle code on the decal on the drivers door jamb too Here's a the link to those codes.

Here's a link to Baz's site, about 1/3rd of the way down the page you'll find tips on what to look for in buying a used PSD.

Hope this helps.

 

[tonkadoctor]

Driver's side sticker in door jamb. Look at the bottom line for the axle code.

http://www.drivetrain.com/Fordtrkratio_posidata.html

Beat me too it

 

[Mike]

3.73's werent offered in the 94-97 model years and I'm not sure that you could get the 3.55's in the F350's.

 

[69oiler]

Gruss' '97 F350 CC 4x4 SRW has 3.55 gears.

 

[Russ]

 

[trackspeeder]

DRW are normally 4.10

 

[apextrans]

If all else fails, mark a spot on the drive shaft with tape or marker or paint or whatever. Lift a rear wheel off the ground & spin it 1 complete revolution. Count how many times the mark on the driveshaft goes around with your 1 rev of the wheel. That will get you close. 4 and a little bit past would be 4.11 to 1. Follow? Hope that helps.

 

[rebel_horseman]

Thanks for the info fellas. I checked the codes and it's supposed to be a 4.10 LSD axle. The truck wasn't much to look at and had some minor sheet metal work on teh front fenders. Couldn't tell if teh ball joints were bad or not though. It was backed in and the wheels seemed to havea noticable amount of toe-out but after driving it around they seemed to be straight. The steering was heavier than my '01 250. There was a considerable amount of blue smoke after it was cranked, but once it ran a short while (approx. 2 or 3 minutes) it went away and after driving it there was only a small amount of noticable smoke at idle, and you had to look for it to see it. Me thinks that 1 or more of the glow plugs are bad. There is a Ranch Hand bumper on the front and back. The interior isn't bad, but the center console is AWOL. Other than that the truck was pretty decent.

If he can make the numbers work I may buy it and be 'Strokin again.

Thanks again for all the help fellas.