[SuprBmwG20]

Hello, was wondering if anyone has changed their diff fluid. Was curious to what the oem weight of the fluid is and the capacity of fluid it needs.

[greekcs]

It seems the spec was changed to G4

[TanzaniteM340i]

Quick question- for the front differential (which I am assuming is an open diff on all M340i) would the correct weight still be G3?

[weinerbarn]

Originally Posted by TanzaniteM340i

Quick question- for the front differential (which I am assuming is an open diff on all M340i) would the correct weight still be G3?

BMW catalog says same for front and rear.

Hypoid Axle Oil G5
Part Number: 83222471487

[Nembus]

Originally Posted by weinerbarn

BMW catalog says same for front and rear.

Hypoid Axle Oil G5
Part Number: 83222471487

Depends if you have the m sport diff or not

[weinerbarn]

Originally Posted by Nembus

Depends if you have the m sport diff or not

True and for the M340i, I believe m sport is standard for the rear diff. So G4 appears to be correct for the rear only. Everything else should be able to use G5. The front diff looks like G2 or G5 can be used. At least that's what I can find.

[Nembus]

Originally Posted by weinerbarn

True and for the M340i, I believe m sport is standard for the rear diff. So G4 appears to be correct for the rear only. Everything else should be able to use G5. The front diff looks like G2 or G5 can be used. At least that's what I can find.

I would look around Supra forums and other forums that share a similar platform to the M340i. OEM fluid is overly expensive for no good reason. I bought some Motul Molygear 75W80 for my rear M-spot dif and some redline for the front. Plan on doing a review on the fluids after I change it out on my car. Along with some new trans fluid, oil change, and brake flush w/ new pads. Got some NGK spark plugs on the way too

[dhock_holiday]

Anyone know off hand how much the dealer charges and at what miles it should be done? On the M3 it’s 1,200 miles and it comes out pretty nasty, do M340i’s have the same rear diff?

[Defpo]

Would this liqui moly hypoid gear oil gl4/5 75-90 be acceptable in both the front and rear diffs? Is there a difference between a G4 and GL4 oil?

https://www.fcpeuro.com/products/gea...BoCaGUQAvD_BwE

[Delighted_Jester]

Originally Posted by Defpo

Would this liqui moly hypoid gear oil gl4/5 75-90 be acceptable in both the front and rear diffs? Is there a difference between a G4 and GL4 oil?

https://www.fcpeuro.com/products/gea...BoCaGUQAvD_BwE

As for your G4 vs GL4 question- G4 is BMW name of their own fluid. GL4 is industry standards. As for the front diff, according to my G20 manual, BMW calls for axle oil G2 for all cars except E53 and E83 w/o N46. The rear axle is G4 for M sport differentials.

[Defpo]

Originally Posted by Delighted_Jester

As for your G4 vs GL4 question- G4 is BMW name of their own fluid. GL4 is industry standards. As for the front diff, according to my G20 manual, BMW calls for axle oil G2 for all cars except E53 and E83 w/o N46. The rear axle is G4 for M sport differentials.

Thanks for that. BMW just had to make it confusing by using a very similar naming haha. Maybe I’ll just go with redline 75w85 for front and rear since it’s compatible with bmw g1-4

[Nembus]

Originally Posted by Defpo

Thanks for that. BMW just had to make it confusing by using a very similar naming haha. Maybe I’ll just go with redline 75w85 for front and rear since it’s compatible with bmw g1-4

For what it's worth I put in the Motul I mentioned in my earlier post and had no issues with my diffs. I put in redline in my front diff. I didn't find anything indicating Redline is compatible with BMW G4 diff fluid. The closest I found was the Motul.

[Defpo]

Originally Posted by Nembus

For what it's worth I put in the Motul I mentioned in my earlier post and had no issues with my diffs. I put in redline in my front diff. I didn't find anything indicating Redline is compatible with BMW G4 diff fluid. The closest I found was the Motul.

This is directly from redlines website for the 75w85 hypoid gear oil. Can’t find anything listed as G5 compatible though

[Nembus]

Originally Posted by Defpo

This is directly from redlines website for the 75w85 hypoid gear oil. Can’t find anything listed as G5 compatible though

Damn good find, this would of been nice when looking for fluid a while ago lol, took me forever to find what would work

[seaurchip]

hello, I am very new to bmw and all these maintenance stuff. after hours of research and looking through manual, I'd really appreciate if you guys could confirm a couple things with me with this g20 m340i!
For those who might be worried, I am not planning to do these maintenance on my own, I'm just trying to buy the products so it saves me money.

1.
m340i comes with m sport differential = SA2T4
and this rear differential takes hypoid G4

2.
does front axle transmission oil mean the front differential oil? the terms in the manual confuses me because I read that the term differential is used when referring to front or rear axle. I was only able to locate information regarding 'rear axle differential oil', but not 'front axle differential oil'. as you can see in the attached screenshot, it says 'check front axle differential oil level' and the next line says 'top up the front axle transmission oil'. in context it seems like they are referring to the same oil but I wanted to make sure. (main group 31 is not shown in the manual)

3.
m340i g20 transfer box? case? oil is DTF1.

4.
front differential oil is 75w85? 75w90? hypoid axle oil G2? (please see the other attached screen shot)

5.
in the manual, the X in chart means 'yes use it' not 'no do not use it X' because I thought it the X means not suitable.. so in the screenshot 'All other vehicles' are good to use 'hypoid axle oil G2'?

sorry guys my english is horrible and my brain is about to explode.
all these infos are scattered and i'd like to gather all info so maybe in the future someone else who needs it can find it easily.

thank you in advance

[Defpo]

Originally Posted by seaurchip

1.
m340i comes with m sport differential = SA2T4
and this rear differential takes hypoid G4

2.
does front axle transmission oil mean the front differential oil? the terms in the manual confuses me because I read that the term differential is used when referring to front or rear axle. I was only able to locate information regarding 'rear axle differential oil', but not 'front axle differential oil'. as you can see in the attached screenshot, it says 'check front axle differential oil level' and the next line says 'top up the front axle transmission oil'. in context it seems like they are referring to the same oil but I wanted to make sure. (main group 31 is not shown in the manual)

3.
m340i g20 transfer box? case? oil is DTF1.

4.
front differential oil is 75w85? 75w90? hypoid axle oil G2?

1. Yes hypoid G4 for the rear diff
2. I believe that is correct
3. Yes DTF1 for the transfer case. Apparently these can be picky about what oil is used. There is an alternative non bmw oil available that is supposedly the same oil as OEM at a cheaper price, this is what I’ll be using.
https://www.fcpeuro.com/products/bmw...ll-83222409710

4. Everything I have seen says Hypoid G5 for the front. Unfortunately I can’t find any non BMW oils that meet the G5 spec. The BMW G5 is incredibly expensive. I will be using redline 75W85 for front and rear as it is BMW G1-4 compatible.
https://www.fcpeuro.com/products/75w...red-line-50104

I plan to change my diff oil and TC oil in about 3 weeks once I get home. Should be at about 7500 miles

[seaurchip]

Originally Posted by Defpo

1. Yes hypoid G4 for the rear diff
2. I believe that is correct
3. Yes DTF1 for the transfer case. Apparently these can be picky about what oil is used. There is an alternative non bmw oil available that is supposedly the same oil as OEM at a cheaper price, this is what I’ll be using.
https://www.fcpeuro.com/products/bmw...ll-83222409710

4. Everything I have seen says Hypoid G5 for the front. Unfortunately I can’t find any non BMW oils that meet the G5 spec. The BMW G5 is incredibly expensive. I will be using redline 75W85 for front and rear as it is BMW G1-4 compatible.
https://www.fcpeuro.com/products/75w...red-line-50104

I plan to change my diff oil and TC oil in about 3 weeks once I get home. Should be at about 7500 miles

Thanks! so Hypoid G2 / 75w85 works for front differential oil. I see some people recommending 75w90 instead of 75w85. Does it have a huge difference / is it compatible?

[Defpo]

Originally Posted by Nembus

Damn good find, this would of been nice when looking for fluid a while ago lol, took me forever to find what would work

Since you have done your diffs already, do the front and rear diffs have both drain and fill plugs?

[Nembus]

Originally Posted by Defpo

Since you have done your diffs already, do the front and rear diffs have both drain and fill plugs?

Yes, the front one will be harder then the rear. The front diff you have to remove the strengthening plate that's held in by like 5-7 bolts and you'll get access to the drain bolt. The fill bolt will have to be accessed through the drivers side wheel well, you'll have to remove the wheel. Here are pics

[D0NVT]

Hey guys, I found that REDLINE 75w85 LS is fully compatible with BMW G4 diff fluid spec but what so you think of filling rear M-sport differential with REDLINE 75w90 LS ?

[stunatu72]

Originally Posted by weinerbarn

True and for the M340i, I believe m sport is standard for the rear diff. So G4 appears to be correct for the rear only. Everything else should be able to use G5. The front diff looks like G2 or G5 can be used. At least that's what I can find.

Where did you find the official info for the m340i on what to put in?

[weinerbarn]

I use ISTA (dealer software) and can pull it by VIN. However you can use other places like bimmercat below but it's mainly for older vehicles. Your 2021 is close enough to 2020. The best thing to do of course is to call the dealer and give them your VIN and they can tell you what to buy and how much of each.

Front:
https://bimmercat.com/bmw/en/search/...iX/USA/31_1559

Hypoid G2 has been replaced by G5 after 03/2020.


Rear:
https://bimmercat.com/bmw/en/search/...iX/USA/33_2304

Hypoid G4 is used in the M sport rear diff.