Not joined yet? Register for free and enjoy features such as alerts, private messaging and viewing latest posts and topics.

Gearbox and Diff drain plug washers

Discuss problems you have had or are having with your Z4
Post Reply
BostonJohn
Member
Member
Posts: 64
Joined: Fri Mar 12, 2021 6:34 pm
Location: Worthing

Gearbox and Diff drain plug washers

Post by BostonJohn » Fri Sep 17, 2021 11:54 am

After going through the forum and speaking to Opie oils I’ve gone for Red Line MTLV for the gearbox and Castrol trans max for the diff but am unsure if I need washers for the drain plugs. I’ve just got 2 new plugs from BMW but only one has an o ring washer and apparently nothing listed for the other plug. I have also just read some diffs do not have a drain plug. Any help please.
Attachments
2F0973A9-AC40-41A1-AF6B-FE4A7F05017B.jpeg
2F0973A9-AC40-41A1-AF6B-FE4A7F05017B.jpeg (106.19 KiB) Viewed 996 times
2.5Si Carbon Black
Silverstone leather
Z3 2.8 Widebody gone

User avatar
BumpyZ4
Member
Member
Posts: 585
Joined: Mon Feb 17, 2020 8:05 pm
Location: New Orleans, LA USA

Gearbox and Diff drain plug washers

Post by BumpyZ4 » Fri Sep 17, 2021 8:17 pm

The one with the green o-ring is for the differential (fill and drain plugs are the same). The other one is for the manual transmission (drain and fill plugs are the same) and if you look close it should have a built in metal gasket. I've read the same thing that some diffs don't have drain plugs but I can't verify it.
2003 E85 3.0i Sterling Gray
KLR 650
Diva Roadster (Kit Car)

User avatar
Jakg
Member
Member
Posts: 367
Joined: Thu Mar 29, 2018 12:36 am
Location: Suffolk

Gearbox and Diff drain plug washers

Post by Jakg » Fri Sep 17, 2021 9:03 pm

I'm not 100%, but I would get new washers. They aren't expensive off eBay - I replaced the oil sump, gearbox and diff drain plugs with magnetic ones.

Check for your exact car, but I think the diff seal is 07119963355 and the gearbox plug has an integrated washer.

BostonJohn
Member
Member
Posts: 64
Joined: Fri Mar 12, 2021 6:34 pm
Location: Worthing

Gearbox and Diff drain plug washers

Post by BostonJohn » Mon Sep 20, 2021 6:37 pm

I checked with my parts man at Chandlers where I got the plugs from and he spoke with a technician who said they self seal and I also picked up a thread on the forum that said the same thing so hopefully it will be okay. It also seems that it’s E86 boxes for some reason that don’t have drain plugs.
2.5Si Carbon Black
Silverstone leather
Z3 2.8 Widebody gone

warmasice
Member
Member
Posts: 875
Joined: Sun Apr 26, 2015 7:16 pm

Gearbox and Diff drain plug washers

Post by warmasice » Tue Sep 21, 2021 12:00 am

My first E46 3 series coupe didn't have a diff drain plug.. It was the 318ci. The 6 cyl 320ci and above did though.
Image

BostonJohn
Member
Member
Posts: 64
Joined: Fri Mar 12, 2021 6:34 pm
Location: Worthing

Gearbox and Diff drain plug washers

Post by BostonJohn » Sun Sep 26, 2021 11:02 am

Both oils changed the RedLine gear oil does seem rather thin but the gear change does seem slightly improved. The gearbox plug supplied by BMW was different to the one we took out which seemed longer and did have a washer so we reused it. Both the gearbox and diff oil seemed okay not too black and didn’t have any particles in either. Cleared out the hood drain plugs while on the ramp as well.
I will probably take off the road soon so all my other planned work will start around April May.
2.5Si Carbon Black
Silverstone leather
Z3 2.8 Widebody gone

Thrustyjust
Member
Member
Posts: 738
Joined: Sat May 11, 2019 10:12 pm
Location: Thatcham, Berkshire

Gearbox and Diff drain plug washers

Post by Thrustyjust » Sun Sep 26, 2021 11:36 am

BostonJohn wrote: Mon Sep 20, 2021 6:37 pm I checked with my parts man at Chandlers where I got the plugs from and he spoke with a technician who said they self seal and I also picked up a thread on the forum that said the same thing so hopefully it will be okay. It also seems that it’s E86 boxes for some reason that don’t have drain plugs.
E86 have a drain and fill plugs on the box but only a fill plug on the diff.
E86 In sapphire black

User avatar
colb
Senior Member
Senior Member
Posts: 1623
Joined: Wed Nov 13, 2019 9:45 pm
Location: Newport, South Wales UK

Gearbox and Diff drain plug washers

Post by colb » Mon Sep 27, 2021 10:21 am

My 2003 2.5 has tapered thread plugs on the gearbox fill and drain plugs, no sealing washers, the diff however has alloy sealing washers on the fill and drain plugs, these alloy washer corrode with age and turn to lace, same on Z3's. Replaced mine on the Z4 and Z3 with copper washers.
Z4 2.5 sealing washers for diff are No 5 in the diagram here
https://www.realoem.com/bmw/enUS/showpa ... Id=33_1147
Gearbox plugs are No 16 here
https://www.realoem.com/bmw/enUS/showpa ... Id=23_0234
Z Shed Cymru member
1999 1.8 Z3
2003 2.5 Z4
1998 Honda Deauville 650
If the forum helped you, why not help the forum back. Thats the Z4 way! :thumbsup:
https://www.paypal.com/cgi-bin/webscr?c ... source=url

fanchazstic
Newbie
Newbie
Posts: 13
Joined: Sun Sep 12, 2021 7:25 pm
Location: Missouri - US

Gearbox and Diff drain plug washers

Post by fanchazstic » Thu Oct 21, 2021 5:00 am

I have an 06 3.0si and the trans had a drain and fill plug with a green o-ring built into the plug (like the plug on the right does. it looks like the one on the left might have one too, but hard to tell in that image). The diff had the same thing but only had a fill plug, not a drain plug. Had to syphon the old oil out with a pump. I haven't seen anything definitive on which cars came with fill and drain plugs vs which only came with a fill plug
2006 E85 3.0si - Sapphire Black

User avatar
enuff_zed
Lifer
Lifer
Posts: 14390
Joined: Wed Oct 26, 2016 11:05 am
Location: Attleborough, Norfolk

Gearbox and Diff drain plug washers

Post by enuff_zed » Thu Oct 21, 2021 9:31 am

Just did exactly this job on my 04 2.2i.

Took out all the plugs and no real sign of any separate washers, just the green bit on the diff one.
as I hadn't read this thread at that point I popped then all back in as they were and no signs of any leaks.

A good tip if you've not already done this - make sure the fill plug will come out first.
Draining it then finding the fill plug is seized is a bit of a bugger!
HQ of 'Norfolk Zed Rescue'.
Always happy to help if I can.

If the forum helped you, why not help the forum back. Thats the Z4 way! :thumbsup:
Image

Post Reply