rear end identification

[Dieselcrawler]

outboard drums means you dont have to disassemble the hub to remove the brake drum.
inboard drums need to have the axle shaft and hub removed to access the brakes.

 

[gonecrazyi]

I've got a dana 61 here. Odd looking axle but has 3.07 gears lol.

 

[lindstromjd]

I wanna say I'm about 99% positive you've got a 4.10 rear end. My '87 has a 4.10 and can hit 72 mph, and that's max for it. Screaming engine at about 3000 rpm's. C6 transmission with no overdrive is not exactly a highway driver. Those gears are great for towing though, no doubt about that.

 

[Dieselcrawler]

I've got a dana 61 here. Odd looking axle but has 3.07 gears lol.

mel was looking for one......

 

[79GLIDE]

I'd guess 4.10. If you can't find tags, there's an old trick you can do to get a close idea without tearing into the differential. Block the front tires and jack up one side of the rear. Put a chalk mark on the tire and another that crosses both the pinion yolk and the snout of the differential. In neutral, turn the tire one revolution counting the number of times the yolk mark passes the snout mark. 4 passes and it's a 4.10, 3 passes 3.54.

 

[rjjp]

I'd guess 4.10. If you can't find tags, there's an old trick you can do to get a close idea without tearing into the differential. Block the front tires and jack up one side of the rear. Put a chalk mark on the tire and another that crosses both the pinion yolk and the snout of the differential. In neutral, turn the tire one revolution counting the number of times the yolk mark passes the snout mark. 4 passes and it's a 4.10, 3 passes 3.54.

If you only lift one side then 8.2 passes would be 4.1, 7.08 passes would be 3.54.

 

[Goofyexponent]

If you only lift one side then 8.2 passes would be 4.1, 7.08 passes would be 3.54.

Exactly, due to the spider gears letting the rearend slip one tire.

Good way to find out if it is limited slip too lol.

 

[Goofyexponent]

Goofy- i am running stock tires. i will try to post pics in an album in the next day or two when im off work. im guessing for the worst on everything, this guy was around 80 i bought it from and had it since new. so being said, he took care of the truck but always expect the worse. i want to drain the rear end, coolant, brakes, etc. anything i can do to make it a happy girl. when i do end up servicing it i will have to look on here and get an idea how to do it. never have taken a rear end apart except for new oil. never serviced one.

Stock tires, 4.10's and a ZF overdrive 5 speed...my truck would top out at about 85 MPH. With stock tires and 3.55's and a ZF...I don't knwo what she will do....never tried.

I am going to say that your truck HAS 4.10's. 235/85R16 tires, at 32" tall, with a 1:1 high gear ratio (-12 ot so % for slip in the TC) and 4.10's puts you at about 72 - 75 MPH at 3200 RPM.

Now, if you want to jack up one wheel in the rear, and try and turn it...this will tell you if it is limited slip. If the wheel spins freely with the transmission in neutral, it's an open carrier. If it only turns a little bit, then binds up...you have a limited slip...or a broken open carrier.

Go to your driver's door, and look on the jam towaeds the back of the cab. There will be a sticker with your VIN on it.

Look closely, it will have an "AXLE CODE" Get either two numbers, or a letter and a number from it. We can try and tell what that truck has in it now, or at least what it left the factory with.

 

[justcuz]

If you do take the time to remove the rear axle cover and change the gear oil, you will find some numbers stamped on the edge of the ring gear. Those numbers tell you the ring and pinion count. Dividing the small number into the big one will result in the gear ratio. An example would be 41-10. This indicates the ring gear has 41 teeth and the pinion has 10 teeth. Dividing 41 by 10 gives you 4.10, thats your axle ratio. You can also visualize your carrier and see if you have a limited slip or not.
If you have a Dana 70 rear axle it may have a number 70 cast in the lower web of the cast center section on the lower right web below the axle tube.
Dana 70 limited slips are said to be pretty good and last quite a while.
I've heard Sterlings limited slip is not as tight and does not work as well as the Dana 70.
If you Google Dana 70 and Sterling rear axles you can find pictures of them, the difference will become clear to you.
Post up some pictures of the door frame sticker and the rear axle, folks here will be able to indentify it for you.

 

[gonecrazyi]

I pm'd Mel about the axle. He hasnt been on in a few days.

 

[84IDI-BERTHA]

thanks you all for the input. I just went under truck and took pics of the axle and door sticker.also, there were a few numbers on the diff but not sure what they mean.guessing part numbers.will post the pics in a few.also, the drivers side position of the axle has a number stamped into it. a lot of the numbers are worn away or covered in gunk that needs a wire brush to read.

 

[Diesel_brad]

Dana 70 axle will have 10 cover bolts
Sterling 10.25 will have 12 cover bolts

As for the info on the tag...
Typically the bolt holding the tag on will cover the 1st digit of the gear ratio.

So if it has 4:10s you will only see the "10"
And if 3:55 you will only see the "55"

If it has a limited slip, you will see an "L" in front of the 10 or 55

The rest of the info on the tag gives plant, build date and so on

 

[84IDI-BERTHA]

got it. i will have to go back and look under it again when i get some other clothes on. sat outside in this 20*f weather for about 40min and was fine in my shorts/sweatshirt. just stepped outside and it like a wind tunnel in my garage. carhart jacket is calling my name i will try posting pics on here in just a second. files were too large, now i made a photobucket.

 

[84IDI-BERTHA]

so i have a picture here of the door panel sticker....somewhat fuzzy to read but hopefully it helps. not sure if the rear end matches this description but like i said, its cold as hell and i wasnt equipped to keep looking for numbers on the crud covered diff.

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this is my diff, its wet because i sprayed degreaser all over, sprayed water to wash it off,and it almost instantly froze with this stupid wind. hahaha, so i couldnt read any easier

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NOTE: this photobucket picture uploading is easy as pie, whomever discovered this has my many thanks!!!

 

[gatorman21218]

My truck would max out at 70 before I replaced the throttle cable. turns out right at the pedal there are two rivets. the pedal had slipped past the first rivet and was grabbing on the second one, giving me only 75% pedal travel. Once I replaced the cable, I could hit the governor in any gear.

So if you cant get to 3300 in 4th or 5th gear, i would recommend looking at the throttle cable.