DIY Giubo replacement
A step by step DIY guide for giubo (propeller drive shaft flex disk) replacement for those that asked and are interested.
1x 18mm spanner
1x 12mm socket
1x 10mm socket
1x 8mm socket
High Temp Grease
Loctite if re-using same bolts
6x 18mm lock nuts (optional)
2x Jack stands (rear)
2x ramps or another 2x jack stands (front)
1750kg trolley jack
Place the vehicle on a solid level surface, use ramps or jack up the front of the car and use jack stands placed in the appropriate place on either side of the vehicle (when using jack stands make sure they are securely placed when lowering the vehicle)
Once the front of the vehicle is secured, use the trolley jack and lift the vehicle using the diff as your support. Jack the vehicle high enough to place jack stands in the appropriate spots on either side of the vehicle, gently lower the vehicle until it had bedded down onto the jacks, keep the trolley jack raised and in place underneath the diff.
Before getting under the car, give the car a shake and check for stability
At the CAT ends, use some CRC or WD40 to lubricate the exhaust nuts and bolts, let it soak for a few minutes, then gently undo the nuts using the 12mm socket and wrench. Do Not Force the nuts as they may break off, instead use more lubricant spray and let it soak for longer, then repeat the undoing process.
After removing the nuts, go to the rear of the vehicle and undo a bracket that supports the exhaust just below the gas tank (petrol tank) using the 12mm socket and wrench.
while your under there, use the 10mm socket and wrench and undo the heat shield bolts.
Crawl back towards the front of the car and gently prise off the exhaust, a few gentle taps may be required, once it is dislodged, it will drop at the front so be prepared, although not heavy it may catch you out if you're not expecting it to drop, use a support or muscles and then gently lower it to the ground, there is no need to remove the whole exhaust so don't worry about the rear end of it all. Having done that, you will see the GIUBO (flex disk) in place, if it looks worn, tethered or damaged in any way, replace immediately, severe damage to gearbox, drive shaft etc will occur if it is left untouched.
If you plan to use an 18mm spanner and a torque wrench then leave the transmission bracket in place, if you plan on using an 18mm socket wrench and a torque wrench at the same time then you will be required to remove the transmission bracket, before you do this, use a scissor jack or equivalent and a block of wood and place this towards the rear of the transmission in front of the bracket and raise the jack high enough so that it just touches the transmission pan - now remove the bracket - transmission will bed itself onto the scissor jack.
Place your vehicle in NEUTRAL so you can manually rotate the drive shaft to get to the remaining bolts. DO NOT spray lubricant on the guibo assembly area or the nuts and bolts, some force will be required to undo the bolts, hence your original shaking of the vehicle making sure it is secure! You can use a rubber mallet (hammer) to tap at the wrench to help dislodge the bolts, once you feel movement then just replace the torque wrench with a socket wrench for easier access. There are 3x bolts that secure the drive shaft onto the GUIBO (flex disk) once all 3 have been removed, go to the centre of the vehicle and undo the centre bearing bracket, hold the drive shaft in one hand for support as it WILL shift, the join in the middle of the drive shaft will collapse the shaft and this will suddenly release the front of the drive shaft away from the GUIBO (flex disk). Place the drive shaft gently on the ground betwen the lowered exhaust. DO NOT rotate the drive shaft while it has been removed and DO NOT bend or twist it.
Now you will have the GUIBO fully visible with a remaining 3x 18mm bolts to remove, again use the torque wrench and spanner to remove them, NO lubricants please.
Take note of how the OLD Giubo (flex disk) was fitted (ie: lettering facing the rear of the vehicle) that way then the NEW one will go on in the same manner.
Fit the NEW Giubo (flex disk) inplace using the same bolts but the nuts are optional as a replacement if you're not going to use loctite. Put all 3 bolts in place with the NUT end facing the engine, use an 18mm spanner and an 18mm socket wrench to hand tighten the bolts and nuts, once done, check for fitment. If all is ok use the torque wrench and the spanner to fully tighten the bolts and nuts. (As a guide, i used the transmission support as leverage for the spanner enabling you to use the torque wrench with two hands)
Coat a fair amount of HIGH TEMP grease on your finger and swab it over the end of the drive shaft making sure most of it goes inside the flange and a minimal amount on the outside of the flange. Lift the drive shaft from the front and the centre and aligning the front of it to the remaining bolt holes in the Giubo (flex disk). While supporting the drive shaft with 1 hand, take the 3 remaining bolts and push the through the GUIBO so that the NUT end is facing the rear of the vehicle, using your supported hand, you can push the drive shaft up and down to align and thread the bolts, now quickly thread the nuts on ( a few turns on each bolt) Now go back to the centre bearing and secure the nuts fully but only hand tight so the bracket is mounted right up against the chassis.
Now use the spanners or socket wrench and secure the 3 GIUBO (flex disk) bolts (the drive shaft will pull in towards the GIUBO, now use the torque wrench and spanner and tighten fully. once completed, return to the centre bearing bracket and fully tighten it to the chassis. Rotate the drive shaft by hand feeling for imperfections, rubbing or other possible problems, if all is ok then lightly clean the shaft using a cleaner and a rag to remove grease and dirt, then refit all the heat shields using the 10mm socket.
Lift the front of the exhaust system and place the ends on the bolts that are attached to the CATs, use the existing 12mm nuts and gently tighten so that the exhaust slips neatly and evenly into the CATs, once fitted and adjusted you can now fully tighten the nuts.
replace the rear exhaust bracket using the 12mm socket.
By now you should have NO screws, No BOLTS and NO nuts left, If you have then go check and see what you have overlooked.
Clean the exhaust using a cleaner.
Remove all tools and pack them away, check under the vehicle making sure all is clear, go to the rear of the vehicle and jack up the trolley jack a little to help remove the jack stands, gently lower the vehicle fully. Do he same to the front if you used jack stands.
If you used ramps, start the car, let it idle for a bit then reverse slowly off the ramps, clean remaining work area of ramps and debris, take the vehicle for a drive slowly, gently increasing speed, DO NOT EXCEED 50MPH.
You should feel smoothness, there should be no imbalance and gear changing is also smooth. If not you may have a damaged or twisted drive shaft as a result of a failed GIUBO (flex disk).
Voila....you definitely just saved yourself a few hundred if not more and you learned something new at the same time.
PS perhaps someone can reformat and insert the attached pictures under the step by step formation, since i'm not that computer literate, thank you!
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