Maserati Gransport vibration

[Lewis Gregory]

Hi, I bought a 2005 GS earlier this year with 74,000 miles on it after owning a 3200 and 4200.The car has a massive history file, mostly with Giallo cars in tunbridge. 2 months and about 500 miles before I bought it, the car had over £10,000 spent on it at Giallo having the sub frame replaced, timing chains replaced, clutch and full service. I noticed on the drive home that the car has a nasty vibration between 4K and 5.5k rpm. I did some reading and drove it 200 miles back to Giallo to get them to
Look at it as I thought it was related the clutch change somehow. They looked at the car and told me it needed new engine mounts but it’s perfectly safe to drive. I’m not sure I buy this as I would expect the vibration to be more linear across the Rev range and not at a specific rpm. To me it sounds like clutch not balanced, can you guys shed any light on it? Any help really appreciated. The car also wore though the edge of the new michellins fitted by Giallo in about 4000 miles, the main tyre is perfect, about 6mm of tread but the inner edge has webbing showing - is this normal?

 

[CatmanV2]

I would trust Matthew and Giallo implicitly. Pretty sure that vibrations could do what you describe with engine mounts, but others are smarter than I

As for the tyres: Well known issue with the factory geometry. Improves turn in. Screws the tyres. New tyres, and full geometry set up with 0 deg toe in will solve that.

C

 

[Oneball]

Modern engine mounts are specifically designed to remove nasty harmonics so it wouldn’t surprise me that you’d get a vibration at a specific rev range.

 

[Moz1000]

I'd suspect the torque tube. This is the shaft that connects the engine to the transaxle. At that mileage its bearings may be worn enough to ruin its balance. It runs at engine speed. A test is to remove it and run it on the garage floor using a pneumatic drill. I saw this once where at a specific rpm the tube started walking across the garage floor.
Moz

 

[CatmanV2]

I assume you mean the propshaft, which runs inside the torque tube. The torque tube doesn't move or rotate.

**** of a test as well. Lots or work. Also, don't pneumatic drills go in and out, not round and round?

C

 

[Gp79]

Do the engine mounts look perished? add a few pics top and bottom if possible.
Also damper on front end of crank could be a possible.

 

[Oishi]

When the engine mounts went on my 4200, I got a vibration above 5k rpm. It may very well be the mounts. However, I must disagree with the judgement that it is safe to drive. When mine failed, the hard oil pipe from the oil pump to the drysump tank was resting on the crossmember, with the weight of the engine on it. At best it will wear through the pipe, at worst it will break the pump body or block. I would get them replaced asap.

 

[Lewis Gregory]

My understanding From the research I’ve done is that the torque tube is not spinning in neutral as the ecu disengages the clutch to be ready for a swift gear change. I looked into this when I first bought the car and pretty sure I disregarded the torque tube based on what I had read.

catmanv2 - yes Matthew seemed to know his stuff, and came very well recommended by the previous owner, but I wonder if he actually reved the engine up or just spotted a small vibration at idle and assumed it was that? When I had a manual 4200 I had my clutch done by Shiltec following a recommendation as I needed a specialist who would balence the clutch. After it was done I asked the chap at shiltec what this process involved and they said they had never carried out clutch balancing on any of them and had no issues. To be fair, that car was fine but I understand it can be pot luck?

id be pretty surprised if the engine mounts were knackered as he would have removed them when replacing the sub frame. If these were not in good shape I would have thought Matthew would have changed them as over £10,000 was being spent sorting everything out?

 

[Lewis Gregory]

Do the engine mounts look perished? add a few pics top and bottom if possible.
Also damper on front end of crank could be a possible.

I’ve had a good look, and they don’t appear perished.

 

[CatmanV2]

Well it's a bit of a guess from here. If Matthew says that's what it is, I'd take his advice. As for clutch balancing, there's a proper way and another way. I've heard of it being done by watching an open door.....

C

 

[Lewis Gregory]

When the engine mounts went on my 4200, I got a vibration above 5k rpm. It may very well be the mounts. However, I must disagree with the judgement that it is safe to drive. When mine failed, the hard oil pipe from the oil pump to the drysump tank was resting on the crossmember, with the weight of the engine on it. At best it will wear through the pipe, at worst it will break the pump body or block. I would get them replaced asap.

I actually asked him if it would be ok to do 3500 miles across Europe, which I then did - fortunately all is well at the moment, and no damage to that pipe but noted - I’ll keep an eye on them. Together don’t look bad at all at the moment:

 

[Zep]

One question. Does it vibrate at 4-5.5k out of gear stationary or only when you are driving?

The clutch is disengaged when out of gear for the first 30 seconds, then it engages to prevent wear of the release bearing. Start it, put it in gear and then back to neutral, then listen for the clutch engaging. A chatter from the torque tube is normal, loud grumbling and it might be a problem.

It is true that the clutches don’t generally need balancing I understand, but there was a batch that wouldn’t balance and so it could be that.

Personally I would try everything else as the clutch is an expensive enterprise. You could also get a second opinion to set your mind at rest.

 

[Lewis Gregory]

One question. Does it vibrate at 4-5.5k out of gear stationary or only when you are driving?

The clutch is disengaged when out of gear for the first 30 seconds, then it engages to prevent wear of the release bearing. Start it, put it in gear and then back to neutral, then listen for the clutch disengaging. A chatter from the torque tube is normal, loud grumbling and it might be a problem.

It is true that the clutches don’t generally need balancing I understand, but there was a batch that wouldn’t balance and so it could be that.

Personally I would try everything else as the clutch is an expensive enterprise. You could also get a second opinion to set your mind at rest.

Thanks, that is very useful, I’ll have a try in the morning. Consider the clutch was changed in April, 500 miles before I bought the car, I would expect Giallo to be reasonable on costs to sort it if that turns out to be the issue. As I’ve said above, Matthew seemed to know his stuff, I’m a mechanical design engineer who has carried out most mechanical jobs there are on my own cars over the last 15 years so not easy to BS me, which he didn’t, just wanted to get the opinion of the guys in here before I spend over £400 on engine mounts.

 

[Oishi]

There is a heat shield on top of each mount that is fairly stout. If there is some clearance between the shield and the sub frame the mount hasn't totally collapsed. Mine had. Under them is an aluminum can type shield that when removed you can press on the bottom of the rubber bulb to see if it is good. You should feel a fluid inside, mine were dry and crunchy.

 

[Gp79]

Engine mounts are probably the easiest / cheapest to replace so probably worth just doing it rule out if nothing else.

 

[Lewis Gregory]

Engine mounts are probably the easiest / cheapest to replace so probably worth just doing it rule out if nothing else.

True, but still over £400 on parts is still a lot to spend if they don’t need replacing.

 

[Zep]

Mounts are £137 each from Scuderia car parts.

 

[Lewis Gregory]

Mounts are £137 each from Scuderia car parts.

Maserati no longer produce them, when you speak with them they can’t get them even though there website says they can, so only option is mounts from a Quattroporte which eurospares have confirmed will fit.

 

[Zep]

Maserati no longer produce them, when you speak with them they can’t get them even though there website says they can, so only option is mounts from a Quattroporte which eurospares have confirmed will fit.

Yes, I was surprised they we’re listed as available to order, thought they might have made a batch. I believe the gearbox mount is the same, but with a different bracket and a lot cheaper.

 

[Twinspark]

IIRC the only difference between the Quattroporte engine mount and 4200 transmission mount is the metal plate on top of the mount, which can be unscrewed and reused from the old one.

The GranTurismo transmission mount has the same mounting plate as the 4200 mount, but I think the rubber itself is taller overall.