defender 90 td5 transfer box

Hi, Ive heard that i can fit a discovery 300tdi transfer box straight into my defender 90 td5 2000/2001 and that this will make the gearing a whole lot better. as i mainly use it for road miles and very little towing, is this correct or advisable. ????????:nospamhere:

Yeah - about to do it myself, you will need to tap two M8 holes for the handbrake bracket, not a big deal stick bracket on and where the holes are missing, drill them.

Will give you better motorway crusing engine speed, low range will be the same.

cheers bud recieved and understood

I will make a sort of basic how to when I do mine, probably in about 2 weeks on Monday it will get done.

Did mine on saturday in the 110. it drives lovely now! at the same engine revs, about 10mph faster in each gear, or the same speed but less engine noise.

all in all, with lunch break/fiddle on the PC break/cleaning up my mess on the drive/fitting cubby box,stereo,floor rubbers,gearstick rubbers etc and then road test, about 5 hours.

hi there, i encounted a problem when fitting mine- i couldnt tap the 2 m10 holes for the handbrake mount as they were already drilled from the side.. i got around this by building a weird bracket that used the existing holes which added a few hours onto the job.. another thing is that both boxes are really heavy!!

stevedehtiar said:

hi there, i encounted a problem when fitting mine- i couldnt tap the 2 m10 holes for the handbrake mount as they were already drilled from the side.. i got around this by building a weird bracket that used the existing holes which added a few hours onto the job.. another thing is that both boxes are really heavy!!

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I've got x-eng disk brake on mine, so didn't need to worry about the two threaded holes

Yeah, they are quite weighty arn't they... about 50kg. fun to push up in on your own although it got in a free bit of chest-press weight training, saved me a gym session

just a quick Q - do the Pumas have a similar transfer box and do they have a disk handbrake? Trew?

Same transferbox, yes (1.2:1 ratio with Q gears)

disc handbrake, no.

thanks for offer of the "how to do" im sure i will put it to good use as it will be a great help. got a mate coming around to help me, but the more info the better.

hi jim did you use a disco 300 tdi transfer box ???? or ????

mat said:

hi jim did you use a disco 300 tdi transfer box ???? or ????

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It was one i won on eblag, only paid £20 for it!

had no slack in it, and didn't leak. bargain.

can't remember the suffix number (without going out and looking at it) but was something like 38G, which according to ashcrofts is a late 300Tdi disco.

I'm well chuffed with the outcome of it though. took the 110 for a blast today, and easily hit 70 in 3rd... not bad for a heavy old bus!

but for general pottering around, noise is much lower.

a (quick) how to:

drain the oil from the current t/box.
chock the wheels (although i drove the front end up onto some ramps, just for some extra clearance)
remove front & rear prop shaft. was easier to totally remove the rear shaf as it kept dropping in the way, front shaft i left connected to the diff as it rests on the crossmemeber)
remove handbrake (it took the whole thing right off, cable an' all. makes things lighter, pull the pin out of the handbrake lever to release the cable)
disconnect speedo drive.
remove the middle seat/cubby box
remove plate under that.
reach down and unplug the difflock wire
slacken off the hi/low lever (i undid the 13mm nut on that funny little bracket thing, just loosened the top nut then undid the bottom one with my fingers)
disconnect the difflock linkage.
there are two 17mm bolts at the top of the t/box (bolt it to the main box), remove these.
back underneath, het a trolley jack and a lump of wood, undo the RH gearbox mounting rubber lower nut, place jack under gearbox, raise it an inch or so, undo the four 19mm bolts that hold the mounting rubber bracket to the transfer box
lower jack and remove it out of the way
another 3 (or is it 4?) 19mm bolts to remove, one is tucked up by the difflock linkage and easy to miss.

now, depending on how physically big and strong you are, either get an engine crane through a door, piece of chain down to the t/box to take the weight, then underneath give it a wiggle, get a screwdriver and lever it off of the main box. it needs to slide back 6 or 8 inches to clear the mainshaft, then lower with crane and then drag out.
or (my method) lay underneath, gently lever the transfer box back, get ready... grab it, pull it off the main box then lower it down onto your chest, drop to floor then drag it out.

refitting is "simply" reverse of the above; either crane the new one up, or (my method again), just push the t/box up into position.
the only thing, is when you initially fit the new box up in and are trying to get the mainshaft through the hole, make sure you don't damage the oil seal. once the mainshaft is through and starting to line up with the input gear, you can let go of the box and get a better grip. some people get some lengths of studding and bolt them to the main box to help line it up and take some of the weight.
I usually squirt a ring of instant gasket around the mainshaft, so it seals around the oil seal should it start to leak ever. keeps all the oil in!

man your a star, you should get a job with haynes.

Ok when I slow down and stop without any gears engaged I get lots of transmission clatter. I know the axles and props are fine (as I've already replaced these) so I'm guessing the transfer box has far too much slop.
It's a 200tdi defender with 35 (soon to be 33) inch tyres.
What's my best option for a replacement transfer box - one from a low mileage TD5?

Hmmm on further inspection this doesn’t appear to be transfer box oil. What could it be as it appears to be coming from the upper area and dropping onto the transfer box. It’s clear gearbox oil.

14platoon said:

Hmmm on further inspection this doesn’t appear to be transfer box oil. What could it be as it appears to be coming from the upper area and dropping onto the transfer box. It’s clear gearbox oil.

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You are asking a question on a 10 year old post?? You migh be better off starting a new post.

Cheers

neilly said:

You are asking a question on a 10 year old post?? You migh be better off starting a new post.

Cheers

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Ah yes well spotted (updated the wrong one)I have a thread running of my own.
Cheers