Thread: The ultimate solution to Td5 vibration / knocking

OK, driveplate is in new condition. removed the inspection cover (3 bolts) at the bottom of the bellhousing and by turning the crankshaft bit by bit using a flashlight I had a good look at the drive plate around each of the 3 bolts. All in perfect condition. Started the engine and looked at the flywheel and driveplate while turning, no wobbling at all.

By the way, brake problems were caused by a not properly closed vacuum hose after removing the EGR solenoid assy. Fixed now.

Since the vibration got worse after installing a CDL linkage from a Disco 1 auto I removed the gearbox trim and panel by drilling out the rivets. I replaced the plastic spacers and fixed the arm better on the CDL splined output shaft as it as sitting loose. With everything opened and Gearbox in N I reved the engine through the vibration zone, but nothing. Then put the box in D and pressed the brakes, and WOW what a noice. It was deaffening, very metallic noice at around 2300 rpm. And it came from the transmissing brake. So something is very loose in there. Have had the problem many times before that no matter what, the transmissing brake adjustment will undo itself after a few days (common issue). I will replace the handbrake with a Britpart conversion kit, going from shoes to a disc. Then will report back.

Getting a little bit confused here. If the truck is braked and isnt moving regardless of in D or N, then the transmission brake and driveline cannot be rotating either, so cannot be the source of noise. So if I understand this correctly, it makes noise only in D when revs go through 2300 and can be reproduced with the vehicle braked stationary. If this is correct, then the issue is in the Auto box or Torque Converter. The only way noises can develop further down the driveline from here is if the vehicle is moving. Other than this it must be a bracket or mounting point touching on something. Perhaps an exhaust mount.

cheers.

It is defenitely loose transmission brake shoes, the adjuster or something else there. It can be reproduced at standstill with box in D and pressing the brake pedal, revving up to 2300 rpm (handbrake not engaged). Have also been driving without the metal plate that covers the transmission tunnel, sound also comes when driving at around 2300 rpm in all gears. Will replace the whole transmission brake with a X-ENG brake disk in the week-end and will then hopefully ever after enjoy the Silence of the Landy.

Probably a loose transfer case counterweight, that big solid lump of iron behind the park brake drum, common to have the nuts holding it on to come loose, creates an awful racket.

Also, running winter grade diesel will make them rattle as it has totally different burn properties, worse than Jet A-1, which is close to kerosene.

JC

Interesting entry about the winter diesel, which of course we have in Norway about half the year :0

Have driven around with the tunnel plate loose the whole week now, am 100% sure that the D1 CDL linkage is cured for any vibration/loose bits, have used a kind of bitumen (is that english) between the tunnel plate and tunnel housing before I rivetet everyting back in place, and used black silicone to close the gap around the D1 CDL housing and the tunnel cover plate. Tomorrow the X-ENG transmission brake goes in and will update the thread on Monday morning.

Getting under the disco to remove propshaft and brake drum immediately revealed that there was play, could move the drum a few millimeters up & down. Removed all the bits, replaced the ever leaking oil seal with a new one, and installed the X-ENG brake kit. Instructions clearly have to be rewritten for LHD Discoveries as the do not make much sense. Also the suggested RRC hand brake cable you need as a replacement is more than twice the length of the original one, so the end result is twice as much rattle sounds as before the conversion as the cable touches both the exhaust and gearbox, and the metal threaded part that protrudes the lever housing transmits happily all the tremours it picked up a long the way. Willhave a chat with the X-ENG lads to see if there is a shorter cable that will do the trick, if not I will have to make some brackets to hold the cable off anything that vibrates, and isolate the protruding end. To be continued.

I have had vibration on my D2, it was the Handbrake shoes vibrate like crazy, solution for mine was adjusting the handbrake to like 2 clicks... its back to being a pleasure to drive...

Thanks. Reading more and more on the subject I will double check my engine mounts. I never checked the height of the mount through the little hole in the bottom. I am convinced the source of the vibration is related to the Td5, and all of them are causing the most vibrations in the 2200-2500 range as that probably relates to the harmonic caused by a 5 cylinder engine.

So the real soluition would be how to smoothen the engine around these rpms - probably impossible; to reduce the effect of the vibrations new engine mounts might help.