Hi All, I’m new to the site so I apologise if I’m posting in the wrong place or this topic has been discussed else where (I have looked to the best of my ability).

The Issue: I had a coolant leak into the transmission of my 2012 L322 4.4 TDV8 (ZF 8HP70) My garage tried to flush it but to no avail, now its goosed. I guess the couch plates have disintegrated. So I intend to take out the transmission strip it down, give it a good clean out and replace the clutch plates, steels etc. This is the biggest job I have undertaken but that doesn't scare me off. I am just strungling to find comprehensive information. I’m hoping your expertise can help.

First off I have the workshop manual for the later L322 but it dosen’t contain any information on how to remove the transmission. I have also looked through the manuals on the Wiki on this site to that same conclusion. Where can I find the removal procedure for the transmission on a L322 4.4 TDV8?

If I’m going to the effort to do this work I want to put decent components back in, all the replacement clutch components I see available for the ZF unit seem to come from china, are these any good? Can anyone recommend a master rebuild set or similar that has quality components?

I’m guessing some of the contamination made its way into the torque converter, I guess I should replace this / get a refurbished unit?

I’m aware that there a number of single use aluminium bolts in the ZF unit and that some people replace these with steel. is this a bad idea?

I wasn’t intending to replace the pistons, should i be doing this?

while I have the unit out is there anything I should consider doing while i’m in the area?

Do a youtube search. There are a couple of blokes who show a complete stripdown. They say you need a special tool for removing the large retaining rings on the drums. You can't just pry them with a screwdiver because its breaks the edges and then it's scrap.
There are a few upgraded parts to make one of the clutches so as it doesn't flex and wear out the edge.
I'm no expert, this is just what I've read.

You are Absolutely right, there are some great videos on youtube for the strip down and rebuild of the box, that's what's given me the confidence to tackle it myself. I'm aware of the special reinforcement tools used to protect the casing, I was going to fabricate my own. My main concern is getting the unit out. I have watched LR Time's youtube channel particularly when they removed the transmission from their 4.4 TDV8 Range Rover, they had to disassemble components in the engine bay to get to electrical connectors and clips, however that was an L405. No idea if the 4.4 TDV8 L322 has the same issue.

KeithBennet wrote:

First off I have the workshop manual for the later L322 but it dosen’t contain any information on how to remove the transmission. I have also looked through the manuals on the Wiki on this site to that same conclusion. Where can I find the removal procedure for the transmission on a L322 4.4 TDV8?
?

I'm not being disrespectful here, but if you need a workshop manual telling you how to remove the transmission, are you sure you have the necessary skills to actually strip it down and re-build it?

I'm an engineer by profession, have qualifications in Motor Vehicle Technology, consider myself a pretty decent mechanic, but I still leave auto transmission rebuilds to the experts!

Have you considered simply replacing the gearbox with a warranted used unit? These gearboxes seldom go wrong, so they're widely available and pretty cheap from specialist breakers.

Jon 1992 RR Classic 3.9 efi Vogue
2014 Disco 4 HSE
===================
Both my fatties now gone...
Previous: 2011 L322 4.4 TDV8 Vogue SE /// 2002 L322 4.4 V8 HSE /// 2009 Discovery 3 2.7 TDV6 XS /// 2004 Defender 90 TD5 /// 1993 110 V8 Snatch Landrover /// 2005 Discovery 3 2.7 TDV6 SE (Aus) /// 1990 110 Isuzu 3.9 County (Aus) /// 1976 Series III Trayback (Aus)

I agree with what Jon says. I did rebuild a Ford 5r55e gearbox myself but I had a step by step guide using an ATSG manual and installed a Sonnax upgrade kit to the valve body. It was very satisfying getting it working again.
I didn't necessarily know what part did what function but it worked out ok.
I would say the 8HP70 has far more critical parts inside and wouldn't be a thing I would attempt.

I hear what you are both saying but the reason I got my L322 rather than another classic car is I like working on cars and I'm treating my L322 as my classic car and doing the work on it myself (it's not my daily driver). I know I would be able to get the box out without manuals etc, but that's not the kind of person I am, I'm a fastidious researcher and believe gathering as much information as possible is the best approach. It would be easier to just get a replacement but where's the challenge in that. I would like to learn about the box and know exactly what has gone into it.

Fair play to you Keith!

Enjoy the process, I'm sure it'll be rewarding. Much better when you can take your time, if it's not your daily!

Jon 1992 RR Classic 3.9 efi Vogue
2014 Disco 4 HSE
===================
Both my fatties now gone...
Previous: 2011 L322 4.4 TDV8 Vogue SE /// 2002 L322 4.4 V8 HSE /// 2009 Discovery 3 2.7 TDV6 XS /// 2004 Defender 90 TD5 /// 1993 110 V8 Snatch Landrover /// 2005 Discovery 3 2.7 TDV6 SE (Aus) /// 1990 110 Isuzu 3.9 County (Aus) /// 1976 Series III Trayback (Aus)