Engine Conversion GU RD28-TD42

[ozy1]

OKAY JUST AN EDIT HERE AS I AM GOING TO ADD A SHOPPING LIST OF BITS WE USED,

TD42 turbo motor,
GU 5 speed gearbox TD42
GU TD42 gearbox crossmember,
GU TD42 accelerator pedal,
GU TD42 radiator
GQ/GU TD42 Overflow bottle
we used GQ TD/TB42 engine mounts for the block, to keep the 2 bolt rubbers
1x diverside modified engine mount,
GQ/GU battry earth cable as old one is too short to read inlet manifold,
GU TD42 radiator hoses,

and thats all i can remember at the moment,




okay, im in no way a mechanic, but im going to pus up this stuff as it may help others, i researched alot of info before we started, and found lot of it to actually be different,

now,
what you need to start off with,
TD42, and you need a TD42 GU 5 speed and crossmember,

What we found, starting the gear box crossmember, there is a difference with the crossmember, they may look the same but, the holes for the gearbox mounts are approx 30mm different,

engine mounts, once you use the GU TD42 gearbox crossmember, you only need to move one engine mount, the engine mount to move is the driver side, it needs to be moved approx 30mm forwards, but if you dont want to, you can always mod the mount that bolts to the block like we did, i do have pics, if ya wanna see em i can email them, the passeneger engine mount lines up perfectly,

also, the RD28 uses 2 bolt engine mounts, where as the TD42 uses 4 bolt engine mounts, and the mopunts that bolt to the blok are also designed to suit the 4 bolt mounts, we resused the 2 bolt mounts, so we sourced some mounts thatbolt to the blok off a TB42 as these are the same as the earlier GQTD42 2 bolt mounts and work fine,

there was a dude on here saying you need to move both mounts, this may be needed if you use the RD28 gearbox crossmember, but i cant see anything else lining up properly,

front tail shaft is too long with evrythinf mounted up, so we need to get this shortened by 30mm or so by the looks of it, and we also have yo notch the gearbox crossmember to clear on full droop, but you have to do this with bigger lifts anyways,

with the bits i hav left over ill try and get some pics up tomorrow to show different engine mounts, and stuff,

anything else i come across ill post up here

[nottie]

you can also cut a plate that bolts to the block ( i used a 10 mm plate) useing the 6 bolt hole on the block and then drill / tap the 4 bolt holes for the mount to bolt to

On a gq the crossmembers are the same and you dont need to change the drive shaft at all you just keep the 2.8 diff/transfer flanges and the 2.8 shafts will go back in. As the transfer does not move

You finding out that the crossmembers on a Gu are diffrent seems funny as the 2.8 gearbox and the 4.2 GQ gear box are the same length Just seems weird that the 4.2 GU GQ gear boxs are diffrent lengths.
Someone night be able to clarify this thats done a GU to GQ gearbox swape as i recall the GUs not being as robust

[ozy1]

[quote="nottie"]you can also cut a plate that bolts to the block ( i used a 10 mm plate) useing the 6 bolt hole on the block and then drill / tap the 4 bolt holes for the mount to bolt to

[quote]

we actually did this, but we bolted the mount to the plate and also welded it, for extra strength

GU 2.8 and 4.2 gear boxes are not the smae length, the 2.8 box and also the ZD30box has a 30mm spacer on the end of the bellhousing, this spacer is needed to allow enought room for the duel mass flywheerl, which are standard on RD28's and ZD30's,
this is why the mounting holes for the rubber gearbox mount are approx 30mm different,

GQ and GU TD42 boxes are not the same either, there are minor differences, these being the overall height of the gearboxes, the GQ's are actually taller, and potrude into the cabin a bit, and also only leave a beesdick of room around the box and floor, the other difference is the gearbox shifter location, there is approx 55mm between them, that being the GU is 55mm further back,

using a GQ box in a GU does not work, as the shifter ends up under the floor, pretty much under the radio, so using a GU box in a GQ qould also send the shifter further which i think would be uncomfortable,

also the shift lever its self is also different between the RD28 and TD42box, so you cant resude the RD28 shifter,

The GU TD42 box are as strong as the GQ boxes, as long as you get a box between late 1997 when the first GU was released and 2002 i believe, as they started having a 5 gear failure between 2002 and 2004 if ive done my research correctly, we ended up using a 1999 model TD42 box

[nottie]

Yeah herd the 5th gear synchro lets go Also the linkages on the low range shifter is diffrent (where it swinges of the gearbox)
When i did my GQ the croosmember was the same as well as others i know that have done this convertion on GQs.
All this info should be a sticky. As youve come up with some good precise facts between the 2


Also when i did mine i welded 4 bolts to the back of the 10mm plate and taped thru the plate and bolts as to get some more strength in it.

Cheers Jamie

[ozy1]

yeah the transfer case shifter is also slightly diferent, but they sall come throught the same hole anyways, so there not really a drama, and if you are gunna used a different transfer, make sure you get the transfer shifter to suit, as they 2 different ones down use the same mount,

the flat for the cotter pin is actually on the revers side of the shifter, ans the shaft it bolts too cant easily be swapped, it might be possible if you dismantle the transfer, but getting the right shifter saves all the dramas,

[ozy1]

also, just another thing we found, as you need to change the accelerator pedal, you need to get one from a GU as they are a slightly different shape, they line up to all the bolt holes, but the cable does not line up with the hole in the body,

so get an accelerator to suit the GU,

we also used a GQ overflow bottle, it bolts straight in in place of the double decker 2.8 version, we also got a new radiator, but this was not a najor need, you could rig up the old 2.8 radiator, but youd need to work out custom hoses, and there is a bypass line on the thermostat housing that needs to connect to the top header tank,

[nottie]

dont know bout GUs but on a GQ you also have to get diffrent accelerater cables plus the hand throttle mounts on the other side of the steer wheel Cant remember why though

[ozy1]

okay, she is alive, we used all the old RD28t loom to run evrything, oil pressure is hooked up no probs,
coolant is hooked up, bit not reading acurately, so we are lookin into this,
tach is not hooked up yet, pob taqp into the computer for it, is starts and drives sweet as, and heaps better than the old motor,