Differential Identification numbers ?

[Grant]

Hi All ,

Sorry if this has been asked before (which I’m sure it has )but I can’t find it .
But are there any numbers on the outside of the diff or on the cogs that show what car it is actually from ?
I’ve seen it says 43x14 so it’s a 3.07 but does that mean it will fit my series 2 ots from the USA?

Thank you in advance for any help

Grant

[mgcjag]

Hi Grant... dont think there is a part number.but there are casting numbers on the case...usually if you look at the rear below the cover plate on the right side there is some stamping...a letter and 2 numbers..my e type has E69.. the 69 is the year but dont know about the letter it dosnt mean E type (also have a 71 XJ6 that has a 71 stamp).....the 43/14 and 3.07 are the ratio of the diff....i know that some have used XJ6 AND XJS diffs in there E types but the important thing to note is the diff mounting brackets that fit on the bottom and hold the fulcrum shaft for the lower wishbone must be E type..there are quite a few that look very similar.....also note there are 3 different types of diff for E types with different output bearing/seal housings and caliper mounts.....also some have LSD and some not....P/L stamped on the tag indicates this or you will need to look inside...the ratio is also stamped on the edge of the crown wheel... hope this helps and gives you a bit more to search on... Steve
EDIT...this might be of use viewtopic.php?f=5&t=5183&p=37432&hilit=4ha#p37432

[mark10337]

I thought it was 4HU that denoted a PowrLok unit.

[Grant]

Hi Steve and Mark

Thank you for your replies, I will try and digest all that , from the pics I’ve seen it has the brackets at the bottom and it has 14x43 on the cog.
It does have a PL on it
I can not see a year or letter on the outside but I will ask when I speak to him again.

I know this may make me sound stupid but how do I not what dif I have ?
It’s a 1969 series 2 from the USA and revs high so it must be a 3:54 but what does the limited slip dif mean ? And are they all that or do they look different ?
I have red the posts saying about spinning the wheels and a LSD will let them spin the same way so I will go and check but does it make a difference ?
What I mean is if I do not have a lsd can I put one on ?

Thanks again for any input

Grant

[Neil1624]

Hello all.

When I restored/overhauled the IRS on my 1966 Series 1 car a few years ago I found some marking stamped into the bottom rear face of the differential casing, they are as follows:

D 66 (where I'm assuming D to represent April & 66 1966) and the differential serial number of 2188 there were also tags with 43/14 indicating a 3.07 diff ratio and I think one with PL on it - alas I have no picture of the latter to check.

Hope that helps.

Neil

[Grant]

Hi Neil


When I get to see it I will keep the month thing in mind

Thank you

[mgcjag]

Hi Grant....for an explanation of LSD just do a google search....from the outside you will see no difference...to tell what diff you currently have you can turn the input and count the output......for example 3.07 input turns for one output turn...you say that the diff you sre looking at has the brackets...but you need e type brackets so use the ones on your existing diff......Steve

[Grant]

Hi Steve

Ok I’m starting to get it now.:-)
Thank you once again for that.

Grant