Hi All
I just made a purchase of a L251 that has genuine 91k on the clock, one owner and is for my daughter to learn to drive in.
It has been painted inside and out in raptor paint, the elderly owner was sick of getting scratches 
I noticed that between about 65km to 75km under acceleration there is a feeling shudder/wobble once above or below these speeds it seems fine.
Could this be engine mount potentially?
If its only at a particular speed the first thing to do is check the tyres and get them balanced, could be a lot of things but the tyres is the first place to look.
Thanks for the reply mate
Itās only happening under acceleration, if I back of the symptom stops even at that speed.
L251, nice! I second DarylW, check tires first. Then tie rods, then ball joints and rack ends. A slightly our of balance or out of round tire will feel worse if one of these items are worn. Engine mount will feel worse at take off and then on gearchanges will not fee right rather than at a speed range.
Are you sure youāre not using more throttle at that speed? Ie just after shifting and trying to accelerate? Seems like a speed where youāre starting to ask the most of the engine ie max load. Try short shifting first and using a lot of throttle from low rpm. Same problem? A bit less pronounced? Do usual service items, good 98 fuel, fuel system cleaner, Italian service. If thereās build up or basic service item issues from elderly putting around, max engine load is where itās going to show up.
+1 on this, I had a really pronounced wobble above 50mph which I eventually tracked down to loose track rod ends from when I had the suspension apart and put it back together in a hurry. Annoyingly I had already paid for front wheel balancing and alignment before I realised this!
So check what you can for free before paying someone else to check the things you canāt!
Thanks everyone for the replies so far.
I have booked the car in tomorrow to get tyres balanced and have a general check of the front suspension gear, hopefully its something simple.
If itās more involved Iāll order parts and do the work myself.
Well today had all 4 wheels balanced and the tyres where inspected for āeggingā with no sign.
They completed a wheel alignment without noting any issues with any components.
The wobble is still there at the same speed, maybe slightly better then it was previously.
I have tried 60kmh in 3rd,4th and 5th. Under acceleration the wobble/shudder is there, when clutch in or not accelerating its not noticeable.
in 3rd at higher revs it is worse then 4th and 5th but exists in all, once you get above 70ish kmh the shuddering ceases.
I have a very busy weekend this weekend so doubt ill get a chance to get car off ground and wheels off, but the following weekend I will have to do some investigation myself
Well I just had a bit of a look under the car (wheels still on) and think I might have found the issue.
The inner cv boot on the passenger site is split and there is a fair bit of play back/forward up/down in it.
nice work man. You think the wheel alignment place may have seen it though and mentioned something.
Yeah pretty slack of them really huh!!
But anyways that is an easy fix, ordered and should be here by next weekend so that works.
I work at a wheel alignment place most Tuesday arvos after my regular job. They do all the jobs the big companies canāt problem-solve (or should I say, couldnāt be bothered looking deep into or just donāt have the understanding to look more deeply into). High-end classic race cars come through that have been looked at by V8 supercar teams and they couldnāt solve the problem because it was outside their norm. My point is, most places just look up wheel alignment specs for the make, model and year and apply that. And if that is all they can do not understand when to add or remove toe to change vehicle characteristics then many will just keep replacing parts till they figure a problem out. Will be interesting to see what it is. I hope it is as simple as the drive shaft. That it is not there when the clutch is in or not accelerating would say ādrivelineā. Certainly a harmonics problems if all the ftont joints and tires are ok.
So today I had a bit of time I pulled the wheel off and loosened some bolts before I couldnāt find my 27" socket, I think thatās the size I need, maybe 29?
Will have to grab a new one tomorrow.
Anyways whilst stuffing around under there the shaft came out of the boot, like its actually snapped inside thereā¦ will get a good view tomorrow if I get a chance to get a socket but yeah, first time I have ever experienced that, going to make it interesting to loosen the bolt on the hub and get the remainder of the shaft out of the gearbox.
30 or 32mm socket is usually the fit for the cv nut.
Als that isn 't fun to do. If you have someone step on the brake while you rattle gun the nut you should be fine. Pity they are a solid disc.
So the shaft came out of the inner boot and I was left with this
I tried wth screw drivers to pry the thing out, used vice grips and had a wiggleā¦
Spent a couple hours swearing 
and being annoyedā¦
Then I ended up putting the shaft back inside and clamping on a vice grip, this allowed the shaft to act as a kinda slide hammerā¦ 4-5 pulls and it was out
Couple more hours fighting the ball joint before I ended up just borrowing a tool for it from a mateā¦
New shaft in and car no longer has any shudders 
Great that you found a solution, now itās time to enjoy driving it.
