Before you do all that painful stuff, on each uj bearing face, remove the circip. and fit a shim cut from a coke can then refit the circlip. You only need to do one shim per axis, not all four. I had the xsame problem and it worked for me .
Have you checked the rear trunions for vertical play, when the bushings in them collapse they can vibrate through the drive train and load up the transverse spring causing stress on driveline components. Cheaper than pulling diff apart and as they require regular maintenance and greasing and bushings in them collapse they are a common failure point and worthwhile to update anyway on any spitfire if you don’t know their age/condition.
Gear meshing in the diff ? If the input/output shafts aren't located correctly due to bearing wear, the gears won't be meshing at the correct angle. Are you able to measure the frequency of the noise and relate it to the axle speed ?
Check the wheel bearings by jacking the cars up and rock the wheel by grabbing the top and bottom of the tire. That bearing can transfer the noise threw the half shaft to the diff am make you think its the out out bearing on the diff. If you feel its the out put bearing on the diff you can dissconect the half shafts from the diff and check if there is play in the bearings from under the car. I would also check the input shaft bearing on the diff.
Sounds to me to input shaft into the diff and that noise is the teeth on back lass I personally would pull the rear diff out and inspect it may just need adjustment
Sounds like diff - pinion loose. Sounds like gear teeth grinding together (when you turned it manually in the first segment of the video). The road test knock sounds like one of the universal joints (you called them "bearings") on a driveshaft. Stop driving it! If a joint goes at speed you're in proper trouble. Yes, I had the problem and a UJ went in my driveway. The handbrake cable got wrapped around the end of the driveshaft and the car locked up. UJ is easy enough to replace. It might also be the hub bearing. Very hard to fix without the right gear. If I were you I'd plan for a stripdown of the rear axle. A note about feeling for play in the UJs: This joint is under lateral stress from the suspension so it might not feel like it has play in-situ, especially when the back end of the car is jacked up and suspension is in fullk droop.. It's a weak design, as the driveshaft is acting as a suspension arm as well as transmitting rotational force to the wheels. Again, I think you'll have to strip it down, or at least pull the hubs / axles off so you can test all of it for play. You have been oiling the trunnions I hope...?
i am suspecting a wheel bearing or the rear trunnion bushings. more likely the wheel bearing. of the two wheel bearings per axle shaft.... i suspect more the needle bearings. it's not a whining sound, or a ticking sound. it's literally a bumping sound, which leads me to my diagnosis. if i happen to be right.... stop driving as further driving will ruin the axle shaft if it hasn't been already. if i am right, there are longer needle bearings available than what the factory installed providing a more beefy roller bearing. it's not a terrible job, but a very very heavy duty axle puller is needed. --- if it's the trunnion bushings, you lucked out as those are vert easy to check and replace. on my car i had a whine which turned into a bumping sound eventually. mine turned out to be the differential pinion bearings eventually gave out catastrophically after whining for quite s0me time. more whine on engine over run. yours is not the same sound i had.
Before you do all that painful stuff, on each uj bearing face, remove the circip. and fit a shim cut from a coke can then refit the circlip. You only need to do one shim per axis, not all four. I had the xsame problem and it worked for me .
Have you checked the rear trunions for vertical play, when the bushings in them collapse they can vibrate through the drive train and load up the transverse spring causing stress on driveline components. Cheaper than pulling diff apart and as they require regular maintenance and greasing and bushings in them collapse they are a common failure point and worthwhile to update anyway on any spitfire if you don’t know their age/condition.
Gear meshing in the diff ?
If the input/output shafts aren't located correctly due to bearing wear, the gears won't be meshing at the correct angle.
Are you able to measure the frequency of the noise and relate it to the axle speed ?
Check the wheel bearings by jacking the cars up and rock the wheel by grabbing the top and bottom of the tire. That bearing can transfer the noise threw the half shaft to the diff am make you think its the out out bearing on the diff. If you feel its the out put bearing on the diff you can dissconect the half shafts from the diff and check if there is play in the bearings from under the car. I would also check the input shaft bearing on the diff.
Send the whole rear axle of for a revamp. Sounds like a damaged crown wheel or something in the diff
At 02:45 my cat got up and walked across the room to check what I was watching...
Sounds to me to input shaft into the diff and that noise is the teeth on back lass I personally would pull the rear diff out and inspect it may just need adjustment
Sounds like diff - pinion loose. Sounds like gear teeth grinding together (when you turned it manually in the first segment of the video). The road test knock sounds like one of the universal joints (you called them "bearings") on a driveshaft. Stop driving it! If a joint goes at speed you're in proper trouble.
Yes, I had the problem and a UJ went in my driveway. The handbrake cable got wrapped around the end of the driveshaft and the car locked up. UJ is easy enough to replace.
It might also be the hub bearing. Very hard to fix without the right gear. If I were you I'd plan for a stripdown of the rear axle.
A note about feeling for play in the UJs: This joint is under lateral stress from the suspension so it might not feel like it has play in-situ, especially when the back end of the car is jacked up and suspension is in fullk droop.. It's a weak design, as the driveshaft is acting as a suspension arm as well as transmitting rotational force to the wheels. Again, I think you'll have to strip it down, or at least pull the hubs / axles off so you can test all of it for play.
You have been oiling the trunnions I hope...?
i am suspecting a wheel bearing or the rear trunnion bushings. more likely the wheel bearing. of the two wheel bearings per axle shaft.... i suspect more the needle bearings. it's not a whining sound, or a ticking sound. it's literally a bumping sound, which leads me to my diagnosis. if i happen to be right.... stop driving as further driving will ruin the axle shaft if it hasn't been already. if i am right, there are longer needle bearings available than what the factory installed providing a more beefy roller bearing. it's not a terrible job, but a very very heavy duty axle puller is needed. --- if it's the trunnion bushings, you lucked out as those are vert easy to check and replace. on my car i had a whine which turned into a bumping sound eventually. mine turned out to be the differential pinion bearings eventually gave out catastrophically after whining for quite s0me time. more whine on engine over run. yours is not the same sound i had.