Differential swap e series to f series

[Conqueeftador]

So iam asking the e guys on this as there's very few f guys that work on the differentials.
I really want to put a different one in my f but there's not too much option on that.

How do the small and medium case diffs compare from e to f?
Prop shaft is not compatible and that I already accepted and I can work with that.
But do the axles match up from e to f? I know that the f doesn't have the couplers but could it possibly work without them by just inserting the axles?
Or take e axles and make them fit on f?

Yeah more questions than answers but it seems like there's little options for me as the e series diffs just seem more available and rebuildable on top of having better options for gearing

Thanks if you stayed with me this far

[wheela]

What f-chassis are you looking to upgrade? Assuming you're not m2, m3, or m4? I haven't seriously looked into differentials, but if you're f-chassis and not already an M car, I'd imagine f8x M3/M4 options would be worth looking into for upgrades.

[Conqueeftador]

1 series fully modified 118i

As far as my experience goes there's really not alot you can do about ratios on any f series.
Yes the m diff swap is very popular but that would set me back to 2's while I need high 3s

Automatic diff on f is usually 2.8 and 3.08 (I have the 3.08)
The only diff that might fit is the 3.91 or 3.32 but they are hard to find as they are both for manual gear and the 3.91 is extra hard to find

[AshwinLB]

F80 dct and manual are both 3.46

[Conqueeftador]

Interesting, but the chance of me finding a used M3 differential in my area are 1 in a million.
And the price for a new one is out of budget

So swapping to e kind of makes more sense still.

[ShocknAwe]

Can you not stick a torsen in there and use brakes to prevent wheel lift spin?

[Conqueeftador]

My problem is not so much with wanting an lsd.
For now I just want to be able to change my ratio
Slow highway cruising in econo I barely even hit 2100/2200 rpm so there's definitely something to say about changing the ratio
There's still alot of headroom.

My problem is 3 fold.

-166lkw doesn't go any further than 3.15
-166lkw has a welded ring
-188lkw manual is hard to find

The first 2 just tell me I need to switch to a 188, the third says that I better find something else that I can find that's more readily available.