PSA: 4.8is Hard 1-2 Upshift "Permanent" Fix with Warranty

[C ///M]

EDIT: I was unaware that FCP switched to store credit vs refunds. Disappointing.

At this point I assume it's common knowledge, but I don't spend much time on this forum, so I figured I'd mention it. For those that don't know, FCP Euro offers an amazing "Lifetime Replacement Warranty" on all their parts (outside of "one-use" parts like cleaners, additives, etc). But that means brake pads and rotors, fluid, filters, oil, seals, etc all have a forever warranty. Essentially:
1. You purchase and install the parts until they need replacement
2. You purchase replacement parts and install them
3. You pay out of pocket to send back the original used parts and FCP refunds you the original full purchase price.

https://www.fcpeuro.com/page/lifetime-guarantee

I use this for all my brake rotors, pads, and brake fluid (since I use Castrol SRF and it's ridiculously expensive) for my street and race cars. It honestly feels wrong sometimes, but it's just way too good a deal/service to pass up.

Anyway, to the point. For the most part, as long as your 4.8is trans has had decent service, the hard 1 to 2 upshift has been identified as being a result of the mechatronics seals and "adapter plug" failing. Luckily, FCP has assembled a perfect service kit:

BMW GA6HP26Z Mechatronic Service Kit - 24152333899KT3

The kit is about $350 (fluctuates a bit) with relatively easy install, or worst case scenario, the labor isn't all that expensive. My 4.8is trans is literally perfect now.

And the best part, if it eventually happens again, you purchase the same kit, perform the swap, and then send all the used components (fluid too) back to FCP for a full refund.

Now this kit isn't exactly a bank breaker, so if you don't feel like dealing with returning everything just to net a little over $300, that's understandable. It helps to have a shipping account.

In that case then, at least FCP put together this convenient kit.

I just bought my 4.8is and I'll admit, it was pretty disappointing that the seller didn't mention any issues with the trans until I was hopping in the car to drive home halfway across the country and they mentioned that "just the first 1-2 shift when cold can be hard".

Understatement of the century. The trans was a complete mess unless you drove the car like Miss Daisy. I literally hated this car; it was undrivable.

Highly recommend this service kit; sorry for the novel.

Sent from my Pixel 8 Pro using Tapatalk

[wpoll]

I don't have the hard 1-2 upshift. In fact, mine's the opposite, it has the common harsh 2-1 downshift. Easy to avoid by not coasting to slow stop but still...

In an effort to address this, I replaced these same seals in my 6HP26 (mechatronic, jumper seals and bridge seal) - zero real difference (to the hard 2-1 downshift).

[LA02MAX]

Funny, my 4.8is 1-2 upshift is the opposite of harsh. It's super smooth but also pretty slow lol. I have already done the full kit you quoted from FCP Euro (at this point, I've sent about $10k their way for this car alone), but it's still a bit of a slushy shift. Doesn't bother me too much because it's fairly rare that I ride out first gear at WOT. Downshifts when I go to pass are lightning fast.