Thread: Transmission Tuning for JLR ZF; 6HP26, 6HP28, 8HP70

I'm a fan of tuning from experience and would love to be getting the best out of our old rig, but is it worth engine and transmission tuning a 2010 3.0 diesel with 255000 on the clock? Is it inviting trouble? The shifts are definitely less than creamy or decisive (and less so when working for a while in low range), and the turbos are a bit oily...

Oh and what does an 8HP conversion set one back? That's enticing...

Originally Posted by Cambo_oldjaguar

On the engine side there's not huge gains to be had in peak numbers with the 5.0L NA. Stock is 276kW/510Nm, tuned is 292kW/532Nm. The intake on the Land Rovers is a bit more restrictive than on the Jags, that seems to be the limiting factor. The biggest difference is the throttle response & low-end torque, as the stock tune is throttled back down low to make it "docile" to drive.

The 6HP28 for the 5.0L NA get's tuned in a similar way to what we do on the Jag XK/XF/XJ, so faster/smoother shifts, revised gear selection strategy & torque converter lockup strategy. Again it's about the way it drives (much nicer) not as fast as possible... it's a much nicer thing to drive, more responsive, more lively.

Thank you very much.

Very exciting

Originally Posted by Stuart02

I'm a fan of tuning from experience and would love to be getting the best out of our old rig, but is it worth engine and transmission tuning a 2010 3.0 diesel with 255000 on the clock? Is it inviting trouble? The shifts are definitely less than creamy or decisive (and less so when working for a while in low range), and the turbos are a bit oily...

I don't think it's any worse for the driveline than stock, there's some arguments it's better for it (smoother running engine, locked up torque converter doesn't heat the fluid as much, etc...)
Obviously if the motor is knackered, it's not going to 'fix' anything, but it's not going to make anything worse either IMHO.
The D3 we did on the weekend had 434'000kms on it, original motor & box, a petrol V8 though so not apples to apples, but it was a noticeable improvement to the way it drives nonetheless.

Originally Posted by Stuart02

Oh and what does an 8HP conversion set one back? That's enticing...

The challenge is sourcing the box and the upper console with the gearshift module and terrain response panel at a reasonable price.
I asked a certain wrecker in South Australia for a quote on the parts to price up a conversion, it was more than I expected it would be.
But let's say if the going rate on a (proper) drive-in-drive-out rebuild on a 6HP28 is $6500, you'll probably be paying a couple of grand more to get an 2nd hand 8HP fitted instead.
My expectation was that an 8HP conversion with a 2nd hand box shouldn't really cost any more than a good 6HP rebuild, but the wreckers want more for the 8HP than I feel they are worth.
The guys in HQ did another 2010 3.0 L319 yesterday, 2nd hand 8HP fitted instead of rebuilding the knackered 6HP, and it worked out cheaper, but you know Australia tax & all...

Originally Posted by Cannon

Thank you very much.

Very exciting

Cheers. Yes it is!

Hello everyone , I am also interested in upgrading from 6HP to 8HP , this question has been tormenting me for a very long time , you can write in more detail what you need for re -equipment , what details and manipulations if possible . I am grateful in advance .

Originally Posted by VIDOC21

Hello everyone , I am also interested in upgrading from 6HP to 8HP , this question has been tormenting me for a very long time , you can write in more detail what you need for re -equipment , what details and manipulations if possible . I am grateful in advance .

Well the parts needed will vary a bit depending on which vehicle with 6HP you have. If it's a Discovery 4 it's quite simple, if another model then a bit more involved.

Aside from the gearbox, gearshift, and other physical components, you will also need to have the engine and transmission tunes modified.
For this side of things you need PCMFlash and a Scanmatik interface PCMflash & Scanmatik – Old Jaguar and the special cables to connect to the gearbox.

Okay just to round out the topic of 8HP conversion, there are some vehicles where it's "easier" to make this because of the console & gearshift being available with the dial shifter.

Discovery 4 L319, 2010-2013MY
Range Rover Sport L320, 2010-2013MY
Range Rover Vogue L322, 2010-2012MY

In this case it also doesn't matter what engine is in the vehicle... could be a D4 with a 2.7, a 3.0, with a converted 3.6 TDV8, or a 5.0L V8

The L320's with the 5.0L V8, or diesel...

The L322's with 3.6 TDV8 in 2010MY, or a 5.0L V8 (those V8 had 6HP right to the end).

Likewise with the Jags, XK/XKR, XF/XFR, XJ, those 2010MY-onward cars with 6HP, an 8HP is a relatively easy swap.

Pre-2010MY vehicles becomes complicated, not just because of the console/shifter integration, but different CAN protocols (29bit vs 11bit). Not impossible to overcome, but more work = more cost.

Please tell me , could you describe the procedure itself and what changes in the block should be made in order to redo the 6 by 8 steps ? I 'll find Scanmatik PCMflash from the guys . According to the mechanics , everything is clear , but pinning the wires and flashing the block needs the help of an intellectual . Maybe you will open a separate topic, I think it would be interesting to many.