Help needed with diff I.D?

(Ian) #1

I picked up a couple of diffs today , they both have no id tag’s , can any one decipher the numbers and letters , look’s like

BIL 007J 9455 4HA 116 7A 13 L60 STL

4HA 016 7A 1913 STL J61 Z 1W D D

Both have 49 teeth

I am guessing the one with BIL on it has been reconditioned ?

(Ian) #2

4HA 016 7A 1913 STL J61 Z 1W D D

I think the 1 may be a 4 so that would make it 49 13 ,

On the other one , that may have been 49 13 , but look’s like someone has taken a grinder to the 49 , that’s the one with Bil 007 J 9455 punched on it !

So from what I have found out so far , I think the 49 is the teeth and the 13 for Overdrive , that would make them 3.77 ration ?

(tony) #3

3.77 is the standard ratio for MOD on most Saloons I have data on

if you have counted 49 & 13 teeth, thats what you have

do you have Parts Manuals for the various Jag models?..they can be the most informative source with regard to numbers

If you check the teeth with a jewellers loop, there would be a noticeable difference in a rebuilt vs used item

(Ian) #4

Thank you Tony
I did pick up a Factory workshop manual Monday , that told me 49 13 was 3.77 ,

I will have a close look at the gears , one axle must be reconditioned at some point , can’t see anyone punching there name and numbers on it for nothing !

Ps , Factory manual even has speed in gears and rev’s for each axle ratio

(Ian) #5

Found out some more from a guy called Alan at AJS Engineering Services .
BIL , is B/L , 007 is the back lash , J may be the machinist initial , 9455 is the serial number , same number should be on the pinion , as they are a matched pair !

Good point on the half shafts too !

New are far superior to the originals and are machined from bar as opposed to the old forged ones.

(tony) #6

Its the Parts Manuals that give the actual part number detail that you provided,
they will likely identify which model they came from…not a MKX, that I can say

was there?..I didnt notice it ?

(Ian) #7

New are far superior to the originals and are machined from bar as opposed to the old forged ones