Greetings all,
Over the past week, I had the zip kit transmission service done to my 2013 LR4(95.2k miles) with the ZF 6HP28 transmission and wanted to share the experience and details. I was inspired by
@Fuji4 and his experiences with it, although his was done on the later 8sp trans that came on 14-16 models. The overwhelming bulk of the work ended up being done by my dad in his much-more-suitable garage but I was involved throughout the process and gathered all the parts and information for him. So, here goes:
Background: we did an ATF drain and pan/filter/fluid change about 6 months ago, switching to the newer two-piece pan and filter design. At the time, I bought the Atlantic British kit and the Febi Bilstein ATF that was compatible with the ZF fluid. The gasket that was supplied with the new pan started leaking soon thereafter and over time, the shifting started deteriorating slightly, with downshifts becoming harsher and upshifts happening too early. Every indication was pointing to either low fluid or improper pressure somewhere so, it was probably a good idea to do this job all over again, with a different/better gasket if possible. Also, we initially didn't replace the connector sleeve and drop the valve body and do the 4 tube seals + double square seal behind it, so now was a good time to maybe do that too? On top of that, I saw Fuji's post about the zip kit and why don't we try doing that too? While you're in there...Also since my dad loves disassembling things and putting them back together with no leftover parts, he was on board. So, off we went.
So as to not rush, we started Monday and finished today. Here is all the information fit to print:
Instructions: For the zip kit itself, we used the excellent instructions supplied. A great walkthrough and backup reference was
https://www.jaguarforums.com/forum/...-zip-kit-install-solenoid-replacement-192881/
Parts:
For the pan/gasket/filter kit, I ended up going to Rimmer Bros this time and ordered their DA2142 kit.
https://rimmerbros.com/Item--i-LR007474BPKITEF
Fluid is here:
https://www.rmeuropean.com/Products/LRN13754-MFG36.aspx
For the seals behind the valve body/mechatronic unit: There are 4 tube seals and a double square seal. I ordered this(it also includes the connector sleeve, which we replaced):
https://www.thectsc.com/products/sealing-sleeve-and-adapter-kit-6hp26/28/32-242-50.html
The zip kit itself: for the lr4, you need the gen 2 zip kit. I ordered it from ebay and got this particular one:
https://www.ebay.com/itm/222531774522
If that link expires, search for 'Sonnax ZF6 GEN2ZIP'. The LR4 has a 6HP28, so you need gen2. The LR3s will probably use GEN1, not sure.
Since the zip kit job will require separating two halves of the mechatronic unit, you will need a new separator plate. From all the research, it is POSSIBLE to reuse the old one if you are careful but to be safe, just order a new one. The catch is that you don't know what separator plate you will need until you take off the pan and read some numbers off of the valve body. For the LR4, there are two versions and this guide is invaluable:
https://www.sonnax.com/tech_resources/179-zf6-valve-body-separator-plate-application-chart
Mine was the A063/B063. Since you won't know until you drop the pan, you don't want to order it and have it take 4 days to ship while your car is in pieces. Transtar came through for me - it came in a day from their warehouse in NJ. They carry both versions:
https://transend.us/search/catalog/guided?pageNumber=1&listType=1&description=separator plate&vhid=4a5294fa02dc&searchType=catalogGuided&priceDisplay=false
Finally, the trans pan gasket. I was going to take my chances with the gasket supplied in the Rimmer kit but
@Daniel Atkinson came through just in time and pointed me to this instead:
https://www.summitracing.com/parts/LUB-LLT-F6R80
I am so glad I ordered this because the flimsy rubber gasket that came with the Rimmer kit didn't look great. This gasket is awesome and doesn't need any sealant.
Otherwise, it is a matter of following the detailed steps laid out in the zip kit(cross referencing the walkthrough in the Jag forum) and taking your sweet time. Every single portion of the kit is in a separate bag, labeled clearly and the instructions are fantastic. FWIW, the torque values for the pan bolts are wrong - 14nm is too much, I ended up going with 10. With the lubegard gasket, it was plenty.
As far as the upgraded zip kit parts - the biggest noticeable upgrade seemed to be the end plugs for the mechatronic unit. The original ones were rather loose while the new ones had beefy o rings in them and had to be shoved in. There were other upgrades too, which are detailed in the zip kit writeup. I elected not to replace the solenoids themselves, but the solenoid orings were replaced with the zip kit.
After all was said and done, filled it with fluid as per official procedure and reset the adaptations using my IID tool. Then, off for a test drive!
There were a few immediately noticeable differences. It shifts noticeably faster now, as well as is in the proper gear much more often. Before, it would upshift early and then get confused when you wanted to accelerate, etc. Coming to a stop, downshifts are much smoother. Overall, it just seems much more buttoned down, executes quick two-gear downshifts on the highway, and seems like no more confusion+no more catching up to what you are trying to do. So far, I am very happy with the results. Also, no leaks so far!
Anyway, hope this helps. This forum is awesome and the collective knowledge we have takes us far, so happy to contribute as much as I can. If I left anything out or can clarify, feel free to ask.
