318is Diff Same as 320i Diff?

[Noodle30]

Saw this 318is diff on ebay just wondered is it exactly the same part as fitted to a 320i? Both are 4.10 open:

http://www.ebay.co.uk/itm/BMW-E30-318is ... 3520977%26

[daimlerman]

Yes,E30 318iS and 320i manual share a 4:1 open diff.

Dead easy to swap if you have access to a vehicle lift,rather more difficult if you like I,are working with the car on drive on ramps or axle stands!

If your existing diff has never been disturbed,the mounting bolts will be torqued to FT levels,and are difficult to get at.Linking two combination or ring spanners and using feet do it for me,but take care to ensure the car is properly supported.

Going back,lift the diff with a trolley jack to get two of the four bolts started,then jiggle the swine up and down to line up the other two.
We have several recorded cases of diff mounting bolts working loose,so a dab of thread lock is a good or/and remember to back there every six months and check for tightness.

Welcome to the zone,BTW.

[Noodle30]

Thanks...really appreciate the reply!

[dave525]

is a 320 auto diff the same ratio too?

[Duke137]

is a 320 auto diff the same ratio too?

Depends what year, my 1988 facelift 320i auto had a 4.10:1 diff. Now it's manual with an LSD

Use the chart at the bottom of this link

http://www.e30zone.net/e30zonewiki/inde ... fferential

[dave525]

cheers

[Andyboy]

Diffs aren't too bad to swap. The biggest PITA is getting the four 19mm bolts back in. Get the front ones in first by a few turns and then the back two.
320i autos had a either a 4.1 or from late 1988, often had a 4.44 ratio diff.

[dave525]

its a 1990 320 auto cab

[dave525]

had a look and its a 4.45 Cheers all