But that's the only promotion I want to see really. The ones that never make mistakes are the ones that most likely cover up or deny mistakes....
Wrong gear oil destroys newer BMW front diff
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But that's the only promotion I want to see really. The ones that never make mistakes are the ones that most likely cover up or deny mistakes....
Lucas
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I'll go with option 2. Someone drained the diff and never put gear oil in it. I don't know if I'd make a video about messing up and then owning up to it.
edyvw
$50 site donor 2025
I don’t dispute his originality.
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Draining any fluid from a vehicle and failing to verify and refill it is a major flaw in a shop's operating protocol. I'm willing to bet they operate like many other average shops: rush it in - rush it out. This likely wasn't the first time it happened, and it won't be the last. I guarantee they haven't learned anything from this, except perhaps to pat themselves on the back for fixing their own mistake.
The shop owner was never honest about their mistake, choosing instead to misrepresent it by saying, "we put in the wrong fluid." Even with ATF, GL-4 MTL fluid, or motor oil, that differential would have been fine for quite a while. Unless you put water, gasoline, diesel fuel, or air in that differential, most other fluids will keep it functioning. This is a shameless attempt at self-promotion. I would have just kept quiet. If the vehicle owner wanted to post about it online after the shop made it right, that would have been their choice.
Just my two cents.
Probably more than three days. Cost too much to experiment with.
edyvw
$50 site donor 2025
I am just saying as his marketing originality. This shop is all over internet. Makes me think if this really happened too.
I mean, hypothetically if it did, that vehicle is probably not tracked, 99.9999999999999% it is not. So, it would survive with Wal Mart branded sunflower oil longer that what he claims. Unless, again, didn’t happen, or they didn’t refill.
There's been a follow-up video from that shop with more detail but the exact cause remains unanswered:
They are not going to know the exact cause by just opening up the differential. They show that the pinion bearings showed galling and they assume it's from the fluid that was used. Lots of BMW techs in the comment stated that this setup and the bearings used are a known problem. Lots of them suggested that the differential probably already had a problem starting before the fluid change.
Some other guy looked up what is recommended on Valvoline's website for this vehicle which is the fluid brand that was installed in the vehicle and that there is no recommendation listed. Supposedly Valvoline does not make a compatible fluid for this vehicle.
I'd say the Valvoline 75w90 GL5 lube was perfectly suitable for that diff that was specified with 75w85 GL5 oil out of the factory.
I think they just got back luck with the timing. It's a common issue with these diffs.
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Can you elaborate?
If this is true, I feel pretty bad for the repair shop in this video.
I'm thinking the drain plug wasn't tight and it fell out in the week following the change....
Wow, so he acknowledges that the slight weight difference of 75W-90 when it specs 75W-85 is likely not the cause, but concludes there must be magic pixie dust in the factory fluid.
And he repeatedly says ONE DAY. ONE DAY. He says all the damage occurred in ONE DAY. I don't buy that a pinion bearing eats itself in ONE DAY because of the difference in gear oil.
That said, I agree they were square in the crosshairs of "ever since"
And he's only encouraging the trolls by taking on comments head-on. Once they know he's reading all the comments and he'll respond to the negative ones, that only serves to make them more active. Trolls don't care about facts, they only want attention.
Still, I am surprised this shop (owner?) is now determined they were at fault and seemingly won't even consider other possibilities. Learning from mistakes is how you grow but creating false mistakes in your head doesn't help you truly learn.
edit: I also feel bad for the tech. I think he did what 99.99% of techs would have done, he just got unlucky with a pre-existing condition
And he repeatedly says ONE DAY. ONE DAY. He says all the damage occurred in ONE DAY. I don't buy that a pinion bearing eats itself in ONE DAY because of the difference in gear oil.
That said, I agree they were square in the crosshairs of "ever since"
And he's only encouraging the trolls by taking on comments head-on. Once they know he's reading all the comments and he'll respond to the negative ones, that only serves to make them more active. Trolls don't care about facts, they only want attention.
Still, I am surprised this shop (owner?) is now determined they were at fault and seemingly won't even consider other possibilities. Learning from mistakes is how you grow but creating false mistakes in your head doesn't help you truly learn.
edit: I also feel bad for the tech. I think he did what 99.99% of techs would have done, he just got unlucky with a pre-existing condition
The tapered bearing he shows looks like any standard pinion bearing. I'd be curious to know how he thinks it magically lives happily in 75W85 but dies a very sudden death in 75W90
Those Germans are wiley but I don't think they've reinvented the physics of tapered roller bearings. More likely they were sourcing bearings from India or similar.....or something about the design places inordinate load on that bearing (think 14bs that get a third pinion bearing to prevent deflection)
I don't either. It was either no fluid or too little fluid put back in, the fluid leaked out because the drain plug wasn't tightened, there were already problems when it came in, or some combination of these. Regardless, I give them credit for making it right, and I don't mind that they've turned it into an opportunity to do a little hey look at us we do the right thing.
He at least heads that off by claiming they got the full amount out -- I think he says 600mL
I have no idea why that happened but I would bet whatever happened it was long before they got the car into their shop.
After thinking about this a little bit more, there is another possibility. The owner did doughnuts or abused the car shortly after the service and then ruined the differential and is taking advantage of the shop. It is a BMW after all, I'm sure all BMW owners are mature and drive them carefully. The shop guy seems sincere and not getting any shady red flags from his words or body language.
Yeah, it was suggested earlier the owner may have been "tracking" it or launching it.
Even so, a properly designed and sized diff should be able to take just about any abuse the power train can dish out. So, that leads me back to a design flaw being more likely. We're all speculating so I understand if others speculate to different conclusions.
