Differential Oil Selection Confusion

[moonlightblue]

I’m unfamiliar with Febi. My opinion is BMW fluid in this case even though it’s overpriced. Could I be wrong? Yes. Do I believe I am taking the least risk? Also yes.

No you can not be wrong,

so it is a matter of saving money

versus

possiblity to waste my valuable time at services,
trying to get parts (that could be potentially damaged) which will also take time
not having the car few days or weeks
paying extra money for car rental
dealing with mechanics who have no idea about repair procedures even authorised service does not know anything about repairing a differential they will probably email Germany as wait answer or try their chances if they are in a hurry
also wasting the Febi and buying oil 2. time and BMW branded that time
dealing with new problems that mecanics will be introducing because of not following procedures.

And so on... Oh my god it is like nightmare I can pay any money for sake of not seeing face of any mechanic. You and Edyvw made up my mind. I will get the crazy expensive BMW oil from BMW dealer and use my syringe and pump it in and forget.

Last question: Do you know know many liters of differential oil do I need for Bmw G20 rear differential?

 

[goblin]

If you listen to chatgpt for such info, you deserve everything that will come to you.

As for fluids - from collective BMW wisdom (which is a nice allegory for Espresso brewed from tears, laments and prayers, on fire fueled by hard cash) - it's quite simple:

- Differentials: regular gear oil matching the required specs

- Transfer case: DTF-1, was it - Original BMW, S-Tec or that rare Shell I forgot the name of, and which is no longer available - whichever you can find. Prices leapfrog each other - sometimes the BMW one goes down to almost S -Tec prices, sometimes the S-Tec goes up to almost BMW prices. I've seen the S-Tec go from $33 to $53 a bottle in 4 months, then down to $43.

- ZF automatic transmissions: ZF fluid only, and forget any nonsense about lifetime and no change.

 

[02SE]

On the wife's Panzer Wagon, I just let the BMW tech (a longtime friend of mine, and former colleague) use the exact fluid speced by BMW.

 

[goblin]

...the exact fluid speced by BMW.

This is usually enough

Almost 20 years ago when the Hydrospace S4 PWC was released, they first advised (heavily emphacized, in fact): "...the ONLY oil that can be used in our engine is /fill some at the time exotic 10w60/...".

The manual actually stated "...use Hydrospace full synthetic 10w60...".

Then some nice guys on the forum asked them "...have you guys heard of the Magnusson - Moss act ?...", and the wording quickly changed with an "...or better" added at the end.

And for a while, "or better" simply didn't exist. Or it wasn't available in the US. Or was it to be marine grade. Can't remember.

So when the requirements are specific enough - you're always good, as you end up with the thing the guys recommended in the first place. Or better

 

[Astro14]

We don’t allow AI-generated content here. Please stop posting it.

 

[brandon9715]

We don’t allow AI-generated content here. Please stop posting it.

I have posted it one time and this is my first warning. I was unaware it’s an issue and messaged you about my concerns.

 

[Astro14]

I have posted it one time and this is my first warning. I was unaware it’s an issue and messaged you about my concerns.

It’s a huge issue.

We reference it here

Thread 'BITOG Standard of Conduct'
https://bobistheoilguy.com/forums/threads/bitog-standard-of-conduct.319568/

 

[martinq]

Thank you very much I now see the video I watched the other video before. Problem was that they used 75w90 Valvoline instead of 75w85 Bmw fluid and damaged the pinion bearing and he is saying that using close viscocity oil isnt enough you should use exact....

The gearbox/diff was not damaged by using a Valvoline product and it was not damaged by using 75w90 GL5. There is a material, design or assembly issue with these diffs which is discussed in the comments and other videos & threads.

I think your diff is also used in the Toyota Supra? I'm sure there are many who use these BMW/Toyota diffs on the track with Amsoil / Red Line / HPL or Volvoline 75w90 or similar. Lots of options out there to choose from.

Research is in order to find out what GL5 fluid provides the best or economical service. There are probably VOA and UOA for this application either on this board or elsewhere. Hypoid diff/gearboxes are not that complicated or unreliable unless there is a flaw in design, mfg, or assembly.

 

[moonlightblue]

If you listen to chatgpt for such info, you deserve everything that will come to you.

As for fluids - from collective BMW wisdom (which is a nice allegory for Espresso brewed from tears, laments and prayers, on fire fueled by hard cash) - it's quite simple:

- Differentials: regular gear oil matching the required specs

- Transfer case: DTF-1, was it - Original BMW, S-Tec or that rare Shell I forgot the name of, and which is no longer available - whichever you can find. Prices leapfrog each other - sometimes the BMW one goes down to almost S -Tec prices, sometimes the S-Tec goes up to almost BMW prices. I've seen the S-Tec go from $33 to $53 a bottle in 4 months, then down to $43.

- ZF automatic transmissions: ZF fluid only, and forget any nonsense about lifetime and no change.

Thanks Price difference is huge. My only reference point about Febi was that I used that fluid in 2019 on a 6 year old and again 40000 miles bmw f30. And, i had no problems at all. Other than price, buying Febi will get me 2 lt of fluid which will give me the chance to repeat the process by re vaccuming 0.9 lt of fluid after a day and pumping the rest of the 0.9 lt new fluid at the bottle which will be like a flush.

 

[moonlightblue]

The gearbox/diff was not damaged by using a Valvoline product and it was not damaged by using 75w90 GL5. There is a material, design or assembly issue with these diffs which is discussed in the comments and other videos & threads.

I think your diff is also used in the Toyota Supra? I'm sure there are many who use these BMW/Toyota diffs on the track with Amsoil / Red Line / HPL or Volvoline 75w90 or similar. Lots of options out there to choose from.

Research is in order to find out what GL5 fluid provides the best or economical service. There are probably VOA and UOA for this application either on this board or elsewhere. Hypoid diff/gearboxes are not that complicated or unreliable unless there is a flaw in design, mfg, or assembly.

I am not sure about Supra using the same diff or not.

That is a valuable information but that Carcarenut mechanic was stating that there was no problem at the differential until the day of the fluid change and then all of a sudden client experienced whining noise and he is admitting that the Valvoline product was not suitable for that car.

 

[martinq]

I am not sure about Supra using the same diff or not.

That is a valuable information but that Carcarenut mechanic was stating that there was no problem at the differential until the day of the fluid change and then all of a sudden client experienced whining noise and he is admitting that the Valvoline product was not suitable for that car.

You're getting the discussion and channels confused. CarCareNut is a different, terrible, YouTube channel that promoted contaminated (dirty) automatic transmission fluid as required for proper transmission operation and long life. I can not tolerate that level of ignorance from someone who should know better (a practiced technician).

Royalty Auto is the channel who posted the gearbox failure video you are referring to. I unsubscribed from that channel because of that video and his obvious ignorance and lack of understanding of lubrication and gearboxes. If the gearbox was drained of fluid and taken to the racetrack, then yes, it's quite likely it could be damaged to failure that quickly.

The damage shown to that gearbox was not due to the quality of product produced by Valvoline. It was not caused by using a 75w90 GL5 fluid.

If you don't have a basic understanding of lubrication and gearboxes and you are listening to "technicians" on YouTube who are failing to understand what they are talking about, you are going to get into trouble.

Any gearbox that specs a GL5 fluid of 75w80 can run 85/90/110/140 fluid in most applications. My caution would be to consider the temperature range of your application. An environment that gets as cold as -40C is going to require a different fluid than one that only sees -15 to +35C. A performance application that is pushed to it's limits (at the track) for extended periods is also going to have different requirements than what you would expect from a fuel efficient, daily driver.

 

[martinq]

Further thoughts on this, this is similar to an engine that specs a 0w20 GF-6a engine oil which can also be run on 0w/5w/10w/15w - 20/30/40/50 GF-6a engine oils. The viscosity difference is not going to damage / destroy the engine if the ambient / operating conditions are taken into account.

Lower viscosity lubricants allow for function in lower temperatures and/or less drag (higher efficiency) but with the potential for more wear / damage. The inverse is also true.

 

[goblin]

CarCareNut is a different, terrible, YouTube channel

I beg to disagree. If it's the guy who goes around new cars commenting on how they're built (the "should you buy" series) - he's unique, and priceless. No one else provides such input on data you simply can't find on new cars that you might end up buying and try to keep afloat past a 36-months lease.

Not sure what he advised about used ATF fluid and how model - specific the advice was, but all-around he's a calm, competent and useful gentleman.

I would be much more suspicious of a chanel that would put a click bait title about a 5-point viscosity difference that killed a front diff in a day, and "own" a case while publishing a video that would more than pay for their mistake in clicks alone.

 

[Rust_Belt_Pete]

Yeah the car care nut video made me raise an eye brow since transmissions have filters that uh... filter stuff like clutch material.

 

[martinq]

Yeah the car care nut video made me raise an eye brow since transmissions have filters that uh... filter stuff like clutch material.

Correct but they won't filter metal as well as the magnets in the pan do. You have to clean those manually for them to keep working, keeping the fluid clean (of metal) and wear down.

 

[moonlightblue]

You're getting the discussion and channels confused. CarCareNut is a different, terrible, YouTube channel that promoted contaminated (dirty) automatic transmission fluid as required for proper transmission operation and long life. I can not tolerate that level of ignorance from someone who should know better (a practiced technician).

Royalty Auto is the channel who posted the gearbox failure video you are referring to. I unsubscribed from that channel because of that video and his obvious ignorance and lack of understanding of lubrication and gearboxes. If the gearbox was drained of fluid and taken to the racetrack, then yes, it's quite likely it could be damaged to failure that quickly.

The damage shown to that gearbox was not due to the quality of product produced by Valvoline. It was not caused by using a 75w90 GL5 fluid.

If you don't have a basic understanding of lubrication and gearboxes and you are listening to "technicians" on YouTube who are failing to understand what they are talking about, you are going to get into trouble.

Any gearbox that specs a GL5 fluid of 75w80 can run 85/90/110/140 fluid in most applications. My caution would be to consider the temperature range of your application. An environment that gets as cold as -40C is going to require a different fluid than one that only sees -15 to +35C. A performance application that is pushed to it's limits (at the track) for extended periods is also going to have different requirements than what you would expect from a fuel efficient, daily driver.

Ops sorry yes I was referring to Royalty Auto Service channel. that mechanic was also talking about Valvoline 75w90 was not suitable for that car. and how do you know that the issue was different? Do you know that car or that mechanic?

Thanks for the info too. Weather will not be under 0 C more than 2 or 3 days a year but will see about 30 -40 C in summer for about 2 months. I do not drift or drive at track at all. It is mostly city and highway driving. 75w85 might also do but then why bmw switches from 75w85 to 75w80 at G20 series I do not really understand.

 

[moonlightblue]

I beg to disagree. If it's the guy who goes around new cars commenting on how they're built (the "should you buy" series) - he's unique, and priceless. No one else provides such input on data you simply can't find on new cars that you might end up buying and try to keep afloat past a 36-months lease.

Not sure what he advised about used ATF fluid and how model - specific the advice was, but all-around he's a calm, competent and useful gentleman.

I would be much more suspicious of a chanel that would put a click bait title about a 5-point viscosity difference that killed a front diff in a day, and "own" a case while publishing a video that would more than pay for their mistake in clicks alone.

I also do not believe that 5 point viscocity difference would kill a diff. then why does Royalautoservice say that?

By the way this product of Ravenol, 1221112 RAVENOL VGL SAE 70W-80 also have the BMW part number that I need as recommendation on the bottle but it is out of stock at the country I am living now.


I accidentally mixed their names while quoting. I ve already watched several videos of Carcarenut too. At one of his videos he gave me the idea to push the axle in with the loose nut on before trying to pry out the wheel bearing in order not bend the speed reading plate of the axle.. he was telling that one of his clients made that mistake while changing the wheel bearing which costed him a new axle. he also gives other valuable info too.

All of them are just simple humanbeings as all of us there is no one in this world who can know everything. If transmission fluid hasnt been changed maybe since 30 years which is a duration close to half a century then ofcourse not touching it can be smarter but, at a less than 5 years old and bit less than 40000 miles young car the best thing would be to change the transmission fluid at every 20000-25000 miles or every 2 years from the time that you change the fluid for the first time to keep the transmission always clean as the car will be getting older.

 

[martinq]

...
Thanks for the info too. Weather will not be under 0 C more than 2 or 3 days a year but will see about 30 -40 C in summer for about 2 months. I do not drift or drive at track at all. It is mostly city and highway driving. 75w85 might also do but then why bmw switches from 75w85 to 75w80 at G20 series I do not really understand.

A recent trend in automotive design is low viscosity fluids and long change intervals, largely for the purpose of efficiency and marketing. This is great unless you want to keep your car or are concerned about premature failure. We can now also make things more efficiently so that they don't outlast their prescribed usefulness. I'm sure it would help the automotive industry if cars expired at 8-10years of age.

Thank you for the details of your operating environment. For those expected temperatures you would benefit (less wear) from a higher viscosity GL5 fluid. I would start at 75w90 and get the fluid tested if you are interested in optimizing for your environment and use. It would be helpful to start with testing the OE fluid if you can.

 

[moonlightblue]

A recent trend in automotive design is low viscosity fluids and long change intervals, largely for the purpose of efficiency and marketing. This is great unless you want to keep your car or are concerned about premature failure. We can now also make things more efficiently so that they don't outlast their prescribed usefulness. I'm sure it would help the automotive industry if cars expired at 8-10years of age.

Thank you for the details of your operating environment. For those expected temperatures you would benefit (less wear) from a higher viscosity GL5 fluid. I would start at 75w90 and get the fluid tested if you are interested in optimizing for your environment and use. It would be helpful to start with testing the OE fluid if you can.

Thanks for the ideas. OE fluid from Bmw dealer is very expensive. As I stated earlier I can only get Febi 75w80 hypoid G1 GL5 and Febi 75w85 Hypoid G3 GL5.

Both has bmw recommendations. 70w80 is for my G20 as I see but it says until 2 / 20 and my car was produced at 7/ 20 which is a little bit confusion too.

75w85 is for f30 which was my previous Bmw.

Trying 75w85 is less risky i think as it is in the middle range between 70w80 and 75w90.

I looked wrong by the way that part number shows 70w80

 

[tblt44]

Don't watch the Royalty Auto vid where they convince themselves a slightly different weight destroyed a Bimmer front diff in a day. I still contend they're idiots and can't watch anything more from them.

I watched that too, did they say slightly different fluid weight ?
I don't remember that
I assumed they put trans fluid or another similar fluid in and not gear oil at all.
No gear oil even the wrong kind or weight will destroy it in a day.