Thread: Gearbox / Motor Vibration SDV6

Originally Posted by brad72

Parts list will most likely be:
- solenoid valves (I could have them flow tested but a full kit is cheaper)
- seperator plate
- mechatronic sleeve
- full set of gaskets, o'rings etc.
- sump filter

For the above parts, your looking at about A$1200.
- dont forget a new sump pan gasket (i went for the thicker one - seals perfectly and no messy goo)
- SONNAX do the valve body kit that includes replacement parts and all O-rings for the valve body - good quality kit with all instruction - ZIP Gen 2 kit
- You will also need the valve body to transmission seals and main pump seal - OEM ZF only!
- new solenoids are best - no point mucking around with old solenoids
- cleanliness is key - lint free rags and lots of carby cleaner (quick evap stuff)

Definitely thorough flush including oil cooler and at temperature to ensure torque converter gets flushed too.

Not sure if the above would fix a shudder - if Torq.C is damaged (i.e. mechanically, or just worn out), then all of the above is moot - then a fully rebuilt ZF with all new parts (including rebuilt valve block would be "cheapest" way to go. depends too if you're hanging onto the car for a bit longer...

Pretty sure to remove the ZF transmission this is a 'body off job - IMHO just too much hardware underneath to get it out any other way (exhaust, access to engine-transmission mounting bolts, cross members, engine mounts etc.)

I also found a shop in the USA (revMax)that sells fully rebuilt valve bodies for about US $1600 that includes a premium for your old valve body - link is below: ZF 6HP21 / 6HP28 Rebuilt, Updated Transmission Valve Body | Revmax My understanding is that once you send them your old valve body, they credit you the USD750 back, meaning for USD900 you have a warranted, professionally rebuilt valve block with all new parts.

Maybe an option? Removing and Installing the valve body is easy and can be done from under the car (on axle stands).

Hope this helps (a bit)

Eric

Thanks Eric, great info. Each shop I have gone to has said the TC is cactus so would add it to the list of parts.

From what I have seen if I separate the transfer case from the transmission and remove it I should be able to remove the box. Certainly not envisaging it to be simple task but doable. I think next will be a full parts list and see where i stand, then make the call on a shop doing the work or doing it myself. The rebuild itself is straight forward enough and having the mechatronic unit delivered rebuilt saves a lot of time. Bushing replacement is simple as is the clutch packs.

I'll post costs once collated.

Brad

1

Originally Posted by loanrangie

Interesting post Eric, I will be keen to know how you find the penrite bmv.

Right, so I’ve completed the ZF6HP28 valve body rebuild.

To recap: new solenoids, mechatronics seal, pump to valve block seals, main pump seal and new valve body separator plate, plus 20l of Penrith BMV and a Sonnax ZiP kit with all new seals

as I said before, rebuild was dead easy, just had to maintain a degree of cleanliness.

put it all back in last week and went for a road test. I also replaced both front and rear diff oils and the transfer case oil, Penrith 75W90 for the diffs and Royal Purple Synchromax for the transfer case.

What at an absolute difference, super smooth shifts, no jolts or harsh downshifts, just sublime torque and effortless power delivery.

definitely worth the trouble.

cheers,

Eric

Originally Posted by Eric SDV6SE

Right, so I’ve completed the ZF6HP28 valve body rebuild.

To recap: new solenoids, mechatronics seal, pump to valve block seals, main pump seal and new valve body separator plate, plus 20l of Penrith BMV and a Sonnax ZiP kit with all new seals

as I said before, rebuild was dead easy, just had to maintain a degree of cleanliness.

put it all back in last week and went for a road test. I also replaced both front and rear diff oils and the transfer case oil, Penrith 75W90 for the diffs and Royal Purple Synchromax for the transfer case.

What at an absolute difference, super smooth shifts, no jolts or harsh downshifts, just sublime torque and effortless power delivery.

definitely worth the trouble.

cheers,

Eric

Glad to hear, just had some RP TC oil delivered this morning and will get the BMV and gear oil on the next RACV 30% off sale.

Great to hear Eric. The Penrite BMV is certainly much cheaper and on paper does exactly the same. I assume it took about 11 litres to do a complete flush?

My shudder continues to get a little worse unfortunately. Almost non existent when cold but once warmed up not so good. Was tempted to do a Penrite flush and add some more Dr Tranny to see i can get another 6 months out of her but from what I have read on the South African forums the flush could help, or accelerate the problem. One of those do i bite teh bullet or hold off.

Kind of wish I hadn't had the box serviced as this is what accelerated the issue which seems is quote common from trolling through LR, BMW and Jag forums.

8 years old now so it what is is.

Hi Eric. Shifting is my only issue with its varying from sublime to clunky. Where did you order the parts from?
Did you follow the workshop manual for the rebuild?
Did you have advice on which seals to replace?
Did you remove and replace the gearbox yourself at home?

Thinking of doing this later next year once I’m over the shock of replacing my intake manifold.

Originally Posted by brad72

Great to hear Eric. The Penrite BMV is certainly much cheaper and on paper does exactly the same. I assume it took about 11 litres to do a complete flush?

My shudder continues to get a little worse unfortunately. Almost non existent when cold but once warmed up not so good. Was tempted to do a Penrite flush and add some more Dr Tranny to see i can get another 6 months out of her but from what I have read on the South African forums the flush could help, or accelerate the problem. One of those do i bite teh bullet or hold off.

Kind of wish I hadn't had the box serviced as this is what accelerated the issue which seems is quote common from trolling through LR, BMW and Jag forums.

8 years old now so it what is is.

yes, the Penrith BMV is $220 delivered for a 20l drum via SCA. As per my other posts, I spoke to the Penrith tech. Department (contact details on the Penrith website) and they confirmed it’s to the same spec as LF6. I’m happy with it so far. I think I’ve got about 8-9 litres left, haven’t checked.

re your shudder, have you confirmed that the transmission is filled to the correct level? The torque converter is a fluid coupling and they need the correct level to function correctly. If not, then the fluid cavitates and this can cause shuddering (assuming of course that there is no mechanical damage to the TC). It seems to me that if you don’t have shudder cold, there is nothing mechanically wrong.

Because the ZF unit locks up at near 0 rpm, you have shudder from the getgo if the TC is damaged / worn.

Once it heats up, it seems to me that there is not enough fluid to allow it to work properly.

The ZF transmissions are correctly filled when fluid just comes out of the fill plug at a temperature of 35deg c.


I filled mine with manual transfer pump initially (cold transmission) until it could hold no more. Then started the car and with a code reader plugged in, monitored transmission temperature and continued to fill all the while cycling through the gears (foot on the brake and park brake on, in each gear about 3-5seconds. I had a mate help me with this, makes it much easier.

The car was sitting on 4 axle stands, level and secure. You need it as high as you can to get access to everything.

We first flushed the atf cooler at the front of the car by disconnecting the quick connects and with the car running, a drain hose connected to the outlet of the cooler into a drain bucket, and also holding the hose from the car into the same bucket. With the car running, pumping fluid into the trans and out of the cooler, about 3-4 litres went through. Stop the car and reconnect cooler hoses.

Restarted the car, and as the temperature increases, continued to fill via the fill point until 35 degrees indicated on the code reader, trans in park, waited for fluid to drain out until just a dribble then screwed the fill plug back in, car off the stands and road test.

Also, before putting the valve block back together, I meggered each of the new solenoids just to be sure, each provided 5.5 ohms of resistance, as they correctly should. Note, tested the, without the mechatronic fitted, as volt meters can damage them.

hope this helps

Eric