Well, this is crappy

[mountainexplorer]

I had always assumed this 14 bolt FF rear under a '74 Crew cab 2wd I had was 3.73's. Then I pulled the cover, and I saw the number 41 and 10 stamped on the ring gear.

Cool, it's 4.10s, and I need a 4.10 1-ton rear for this other truck. I pulled the old rear out, and went to put the 4.10 14 bolt in.

"I wonder what date reads on the ring gear" I wonder. I glance one last time before I bolt the cover on, seal it and install it and finally would be done with this truck.

73 for the year... hmmm... and a 10 for the pinion tooth count... no wait... that 10 is a month. October of '73. Ok.

Wait... if the 10 is part of the date code... what's this over here before the stamped 41. AWWWWWW CRAP!!!! It's an 11... it IS a 3.73. 11 and a 41... spaced apart further than usual.

Now I'm screwed on my "quick axle swapover".

The moral of the story... make sure you know what numbers your looking at before making life changing decisions for your axles. My glance was deceiving.

 

[sled_dog]

thats why I ususally count the teeth too

 

[mountainexplorer]

Only 1 tooth makes all the difference, too. 11-41 vs 10-41 So close, yet so far.

 

[84_Chevy_K10]

I'm deeply confident that despite this dilema, you have more axles

 

[mountainexplorer]

The front in the truck is now 4.10. The rear was 4.56. I now have a 3.73 rear. I have two 4.10 1-ton 14 bolts with factory Gov-Locks, one for the plow truck, and the other I was selling to s friend for his '72 K5. Looks like I'll be swiping the one I was selling to him since he hasn't bought it yet anyway.

Slight setback, but able to be remedied. Just will make a day chore of an axle swap into a weekend deal. My fault for not being more alert as to what numbers are what.

 

[diesel4me]

I bought a 71 CST K5 blazer that had a 3.08 rear and a 3.73 front axle--evidently someone just swapped any ol rear axle in from the boneyard--I paid 300 bucks for it so I wasnt too upset about it--I had another 3.73 axle from a suburban--but the "Redneck Way" I "fixed" it was to use different size tires on the front VS the rear to help make up the difference--it drove me thru a whole winter that way,and I ended up selling it the next fall--I gave the new owner the rear end with it--he moved to texas and the the rear axle at his fathers house,fuguring he'd never really need 4wd there,and the truck drove ok with the mis matched tires--so his dad called me and told me if I wanted it back to just come get it--I sold it to another guy a week or 2 later for 75 bucks!....
I hate trying to figure out ratios by counting teeth--I always get cross eyed!..and finding the factory stamped codes arent much fun either(on the axle tube--usually never stamped where they tell you to look)and if it ever had a "tag" on the cover bolts,you can bet it wont be there when you want one to be--and like you found out--its kinda tricky to read whats stamped on the ring gear--not hard to "goof" at all........