10 bolt ?

hi trying find out info on my 8.5 10 bolt rear end on the axle tube numbers are. phg71581
found a ph code might mean 3.55 gears butg cant find it with phg.when i got this rear friend said it has 3.73 gear and its out of a camaro .thanks

 

what ratio is it? count pinion turns to get one full turn of both axles

 

PH is a small ring gear 3.55 posi in 1968

The way the codes work there are two letters then a division code, G is the div code for Chevrolet, so PHG could be that rearend.

or not.

 

havent counted the ratio yet. but when i cruise around 40 my tach is at 2200-2300 rpm and i am runnin 15inch g-78 tires.would like to know what this rear end came out of

 

pull the cover look at the gears they will have a # on ring gear like 41.11= 3.73 or 39.9= 3.55 or 3.54 something like that and if it is a 8.5 it should be post 72 or right around there and if it came with leaf spring perches stock it will be F body or nova

 

if it is pre 72 it will most likely be a 8.2 10 bolt

 

it had leaf spring perches

 

I think 8.5 s were used after 73 in novas and maybe 71 72 in camaros and fire birds not absolutly sure, other wise if it is late 60s it is an 8.2 from nova or camaro firebird all were same dimensions 67-69 f bodys 68-72 novas

 

was told by my friend it was supposed to be 71-74.camaro pontiac wouldnt the numbers tell the year

 

Yes there is a book ,Chevrolet By the Numbers, that gives decoding info, or there should be something online to figure it out. My books at my shop or I could tell u.

 

Squirrel could be right

 

I have the Chevy parts book that lists the codes, the two letter codes for all 71-74 camaros start with G.

so I doubt it's from a 71-74 camaro.

 

thanks.

 

like he said, divide small number into big......

 

found this
but this is for a pontiac rear it says the ptg is posi and phg is not.could this be right?.when im driving does not feel like a 2.56 rear and i remember leaving 2 marks when i lit the tires upguess i will pull the cover to find out what i really have.

<table border="1"><tbody><tr align="center" valign="bottom"><td>1977</td> <td> 2.56</td> <td> PHG</td> <td> PTG</td> <td> FB
</td></tr></tbody></table>

 

get a axle housing flange to flange measurement since it sounds like the spring perches are gone.

 

Like squirrel said, just count the pinion turns. That way you don't have to open it up. You do this by jacking the back of the car up, support on jack stands and spin one of the wheels by hand. Look and the opposite wheel and see if it is turning the same direction as the one you are turning....if it is turning the same direction, you should have a posi....if it's turning the opposite direction, its an open rearend.
Now, to find what ratio the rearend is...if it was a posi ( both turning the same direction) with the car in neutral, spin the tire one revolution while watching and counting how many revolutions the pinion spins.
Now, if it was an open rearend (one tire spinning the opposite direction) you need to "chock" or stop the other wheel so it won't spin while you are spinning the you are using to count. With the other wheel chocked, you spin the wheel TWO complete turns and count the revolutions the pinion makes.
Squirrel, correct me if I'm wrong.

 

it was 61 inches spring perches are not gone this is a direct fit for 49-54 chevy cars..