My car has developed this terrible shuddering knocking sound that literally shakes the whole car when ever i try to move the car at all.

It doesn't happen at regular intervals and will be okay for maybe a few meters then "THUNK" , then okay for another meter or two then "DHUNK", its very loud and even makes the whole car shake. I thought it might have been a damaged CV joint so i replaced that, but that has not helped at all.

Also in case this helps, when this first started happening it would be much less frequent and only happen when the wheel was turned slightly and now and agin while i was going down the road it felt like the wheel had detached from the car and the steering would go like the wheel wasn't connecxted to the car at all, then it'd kinda pop back into place and all would be fine for a while.

At the moment though its in a real bad way and i fear to move the car at all in case i make things even worse.

It seems like the driveshaft is slipping where it meets the gearbox/diff (not sure what that part is).

Any ideas or comments would be fantastic as the car is a non-runner until i sort this out.

 

I was going to say CV as well, did you replace both front CVs? If it is an open differential and one is broken, it could possibly cause intermittent slipping....It's possible that you have broken something internal to the transmission as well. Tough to say, can you get the drive wheels off the ground and freely rotate the wheels by hand or do you encounter resistance?

On the steering things, make sure you reach up and yank around on all of the steering parts (tie-rods, steering rack, column, etc.) to see if they are tight/loose. If something in the steering is causing the issues you describe, something must be broken & should be readily identified. When you steer left/right, is there any freeplay? (i.e. steering wheels moves, but tires don't)

 

ffokay, another little update.

I put a big wooden board on the grass and jacked up the car on that and under the advice of my mechanic i then tried to run the car with one wheel up in the air.

Results:- Knocking is still there and the wheel will move around but its very jerky at first but when you get the wheel up to a bit of speed it tended to smooth out a bit. But when i tried this with the other wheel up (and the drivers side back on the ground this time) the exact same thing happened, same knocking and evened out when it got up to a bit of speed. Basically identical for either side.

reply to sstlaure:- if i try to rotate the wheels by hand when in neutral, and one side jacked up, then i do encounter a resistance but it comes and goes, sometimes totally stiff and almost impossible to move then it'll slip again and move round freely then it'll get stuck or very stiff again. this is the same for both front wheels

This led him to believe that either both driveshafts are equally rounded at the place they meet the gearbox/diff, or that the problem is with internal stuff in the gearbox/diff itself.

When i get the chance, i'm going to have to pull off both the driveshafts and check for any wear and if they both look okay then unfortunately a whole new gearbox will be needed. He said they're no point dicking about with the internals of the gearbox as new parts won't be available.

As for the Cv joints, i put a span new one in the drivers side and it made no difference, therfore i guess that a new one on the other side won't do anything either.

I'll post any new information up here in this thread on my progress.