Automatic Gearbox broked

I have a 1989 Range Rover Classic 3.5V8 with a 4 speed ZF4HP Auto Box.

I recently lost all drive, which would come back on occasionally, but this appeared to be OK after a new filter and oil change. A few weeks later I've lost all forward drive ( engine rpm doesn't even change when selecting drive ) but can use reverse ( well untill I reached a wall ).

There are a couple of second hand 1992 ZF4HP gearboxes available, but am not sure if it's a direct replacement. My car has the old cable sppedo drive, and think the 1992 models had an electronic one.

Can anyone advise me if the 1992 box could be used?

as long as its v8 it will fit perfectly speedo is in transfer box so makes no difference ,you need to measure from gear box mounting face back to torque convertor drive bolt hole face ,measure from engine mounting face to rear of drive plate ,this measurement needs to be at least 1mm smaller than gearbox to t/c measurement otherwise oil pump in gear box will be damaged, your box has burnt clutch pack A which is first clutch pack behind beii housing and oil pump plate and is an easy fix for competent person as dosent requir stripping of main box

Great, thanks for quick reply. I'll take off thee car and have a look before buying another

any ideas who sells these clutch packs in the UK

ashcrofts do personal i would buy a recon unit if you plan to kep it or get a good s/h unit

why recon usually its only a few parts that wear if youd seen inside many you would know auto is better to repair than many manuals that do have wear throughout,pm me i can get parts for clutches etc at trade

Thank you both for replies. Have found Ashcrofts website, they offer a Master rebuild kit which includes complete set of clutches for £195 +vat or a full recon unit at abou £675+vat. My budget won't allow for a recon unit. Must admit they have a great selection of diff lockers etc on the site
I've finally got the car over a pit and will strip and inspect as soon as time permits. I've had a look at how the box is built and agree that perhaps only a few parts will be required, and that this will be a better option than risk fitting a second hand unit only to experience same problems in few months. One of my friends who was trained as a mechanic years ago seems to understand auto boxes and has offered to help.
James I'll PM you when I know what parts I need

I'm currently stripping down the ZF auto box, Clutch pack A was definitely easy to access, but have noticed some wear in pack B, looks like a very thin gasket type spacer damaged. This came out fairly easy with a couple of hooks.

I think at this stage it is worthwhile stripping everything to inspect as there has been a fair amount of debris about, but am stuck getting clutch pack C removed. My landrover manual refers to special tool LST117 or LRT-44-504. Is there any way to remove without this tool? if not, where I can get one?

to get to clutch c which is two clutches with one way clutch (sprag clutch) you have to first remove valve block and 4 x circlip and springs and tube seals cealing clutch feeds ,then pickle out center snap ring ,and pull out piston clutch c is in basket with clutch d behind it it comes out as complete assembly ,but can be a little fiddly putting back as basket with clutches has to be aligned and held with out clutch c falling out ,if clutch pack looks brown okay black replace you can get individual plates frition and steel

Thanks, it was tight to get out. Clutch pack A was black, no friction material left, Friction plates on B starting to come apart, C, D + E OK, and friction material crumbling on F. I guess it's best to replace all.

Before losing forward drive completely which appears to be due to the A clutch, I had no problems when selecting drive, that is none of the failing sprag clutch symtoms, as the gearbox is now dismantled, is it worth considering changing the sprag clutch?

you can easily test them the one in clutch c is most prone to fail hold it between both hands and turn it then back it should lock and only turn one way instantly,if it doesnt wash in clean petrol ,paraffin etc and try again if works ok if no better replace,the rubber tube seals can be fitted upside down to give good seal as is only small part that does sealing to clutch pistons,just replace poor clutches ,test pistons on burnt or poor clutch using low air line to much will blow seal out without clutch to press against ,clutch f will need screws replacing loosely to test

I'm glad you are getting the help you seek, I would'nt know where to start. Just out of interest what's the mileage on the 'box?

your gonna have to do sooooo much cleaning to make sure that govenor doesnt block up when you start using the box again.

Good luck with the the rebuild and I hope it works- you have some ball to try it!

I nackered mine while putting it back in as I broke the oil tabs as I didn't know about them so put the tourque converter in the box before fitting!
I am running a zf4 from a 1998 disco but did have to change flywheel and torque converter so if you get a later box make sure you get the flywheel and converter.

I lost the insp cover if anyone has one for sale?

Got a complete auto box .

Khryztal said:

Got a complete auto box .

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So have I but it's fitted to my 90 

you might need it k-man

Thanks everyone for advice. It's a little scary, but seems to be fairly straing forward The box had done about 140k before failing. yes, some major cleaning required to get all the A clutch debris cleaned, it got everywhere. The dishwasher has proven to be able to clean more than dishes

I have some concerns about the One Way gearset in the C clutch. it turns one way and locks the other, but if I fiddle with it, I can sometimes make it turn both ways. Is this a sign of imminent failure? I don't fancy taking the box off again if I can avoid. anyone any ideas where I can get a sensibly priced replacement?

diehard classic said:

Thanks everyone for advice. It's a little scary, but seems to be fairly straing forward The box had done about 140k before failing. yes, some major cleaning required to get all the A clutch debris cleaned, it got everywhere. The dishwasher has proven to be able to clean more than dishes

I have some concerns about the One Way gearset in the C clutch. it turns one way and locks the other, but if I fiddle with it, I can sometimes make it turn both ways. Is this a sign of imminent failure? I don't fancy taking the box off again if I can avoid. anyone any ideas where I can get a sensibly priced replacement?

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If after cleaning it can be turned the other way at all, dump it and fit a new one.