Had to take the car out yesterday after it has been sitting for a few weeks. I am still impressed with the transmission. It is by far the smoothest gearbox that I have ever owned or driven. The shifting is seamless in any application whether it be just in drive or with the paddles and even in S mode. During passing or acceleration where the engine rush is there the gearbox handles it extremely well. Also whether it is cold or hot doesn't seem to affect it's performance. Just throwing in my 2 cents here.

 

I find mine to be a bit jerky when starting out in the lower gears. After getting to the higher gears it is silky smooth. Wonder if mine has an issue?

 

I believe Jagtoes has a different gearbox in his 5.0L.

 

Ahhhh. OK, thanks.

 

Had the same issue as you with my 05 Super V8. I changed to oil and filter via the recommended procedure from ZF, so not a complete flush. This was back before anyone confirmed that Mercon was the same as liquid gold and a full flush was extremely expensive.

Anyway, it solved the issue, without the need to reset or reflash the transmission.

I also had the "squawk". Early Jaguar TSB indicated to put in a specific additive. This is no longer necessary as the ZF fluid contains it.

So three things changed from "Sealed for Life" -
no more additive -
depending on the driving style, ZF therefore recommends a transmission oil change every 80 000 to 120 000 km, or after 8 years at the latest -
Mercon SP is a suitable substitute for liquid gold.

See this sticky on the X350 forum if you're interested in learning more:

https://www.jaguarforums.com/forum/x...2/#post1790760

 

The 4.2 has a 6HP26 box, whereas the 5.0 has the 6HP28 (with faster shifts, quicker torque-converter lockup and the ability to skip gears when shifting rather than having to shift sequentially)

 

Apparently a number of the earlier 5.0 cars still had the 6HP26, there was a thread on here about this fairly recently.

 

So I keep hearing, but if it's true, I don't think there were many - probably some of the first 2009 cars here in the UK. There are often some oddities as models change. But I suspect most of us will never encounter a 5.0 without a 6HP28.

I wonder how you'd spot the difference if you were looking at an early 5.0?

 

The build sheet from Topix identifies the gearbox by model number. It is the first entry under features.

 

Aww, yeah. Durrr...

 

It could just be bad data but judging by Topix at least the first few hundred 5.0 litre cars had the 6HP26 so I wonder what the cutover was? B32956 is attached.

I am really surprised given that they specifically mentioned the 6HP28 in the original press release for the 5.0 litre. Perhaps they had supply issues?

 

I'm B34136 and have a -28 transmission according to TOPIx. I wonder at which VIN the changeover happened.

 

I don't think it's a simple as before and after a certain VIN. I've reason to suspect that body shells were built and stamped with VINs but didn't get built into finished cars strictly in sequence. As I posted on another thread, I know a local chap with an XKR with an earlier VIN than mine that SDD identifies as a MY2009 car, where as mine is identified as 2008. There are some 4.2 cars with VINs later than the supposed cut off, and 5.0 cars with earlier VINs.

As for 5.0 cars with the 6HP26, they maybe just ran out of 4.2 engines before they ran out of 6HP26 transmissions.