Odd noise/rattle from rear of car - any ideas?

[griffith400]

Was out enjoying the Fabulous weather on Saturday and mid-run developed a strange noise (heard even above the thunderous twin gattling gun Griff Exhausts!)

It's an odd one to describe but is a sort of a creak, similar to that of a stretching or worn cable. It seems to come from around the centre to rear of the car and only when moving. Was doing it mostly when pulling away but also when the clutch was depressed or when out of gear. This would seem to rule out Gearbox but I assume still could be diff or propshaft related? Maybe even driveshaft? However, didn't sound like a heavy metal/grating noise from those sort of things and more rattly? Doesn't seem suspension related as smooth/rough road seems to impact the same.

On Sunday morning I jacked it up and got under the car and the only thing I could find was the exhaust centre box shelf, some of the bolts that go through rubber bushes were a little loose. Tested it on the road but as on Saturday, the car was fine initially while still cold but one all warmed up, the noise returned??? Car still feels perfect, even on hard acceleration (was worried about trying that!) so really at a loss.

Hard to explain without being there but thought I'd ask just in case somebody had come across something. I guess it may need to go to a TIV Expert but our garage in Scotland is neither convenient nor will it likely be cheap

[THREEFISHORANGE]

Could it be your suspension springs if they are creaking?
Or have you recently replaced some bushes??

Seems strange as it does it when it's warm??

[5.0ltr]

Any noise if you bounce the car when stationary?

[griffith400]

Thanks guys,

TBH, I can barely make the suspension budge, never mind bounce it I had the car setup on Protech springs and dampers 2yrs ago and it's pretty much rock solid. I tried but it don't move much. Thing is, the noise happens when on smooth or undulating road. Also, it's obvious when I move from standstill but even if I'm really gentle (ie, not a normal squats down at the rear tear away!) it still makes the noise, so I don't think the suspension is the prob?

I've just tried moving it back and forward out the garage and it's not happening, I guess cos it's cold.

I'm worried it's something like the diff as it's the only thing back there, other than the exhausts, that would heat up during use?

Steve.

[HRG]

Check the bolt that holds the exhaust to the crankcase, that can creak just like the suspension when it's hot if it's loose.

[Tildo430]

I've had two noises from the rear. The first a rattle ws diagnose quickly and cheaply as a brake pad retaining pin having broken off casuing the pad to rattle against the disk and the second, a whine/squeek is being looked at this week whilst in for a service. Early indications are that it could be the handbrake getting a little sticky as the brakes warm up.

[olemisery]

I also have a creak from the rear that only appears when hot , have protechs also and have put it down to these , creaks on pulling away and over undulating roads and mild bumps . Seems like it is the first few mm of take up on the suspension . Drives me nuts !! You say your Protechs are rock solid , mine were excellent but now are 2 1/2 years old and very bouncy . Sorry no more help .

[griffith400]

Thanks Andrew, this is more of a metal creak (like an accelerator cable that is strecthed / about to break) rather than a rattle though.

Rob, thanks for the tip on the exhaust / crankcase bolt. Don't know that one so will have to get under the car at the weekend and have a look. I thought the sound was further back so hadn't looked that far forward so need to investigate.

Paul, thanks for the help (looks like you've had to do loads of work on your car, sounds like its been worth it). I don't think this is suspension related TBH going by when it happens but it's possible. The Protechs made a huge difference to the car, Jools at Trackcar recommended them and matched them to 450lb front / 300lb rear springs and I can barely get the thing to twitch by leaning or lifting the wing!

Thanks for the help guys. I'll try and have another look at the weekend, it's difficult to find a fault that only happens on the road & when hot which is why I thought I'd ask for advice. May end up having to spend some pennies with our Indie I guess

[Uncle Fester]

Check if the anti-roll bar mounting bracket on the wishbone is beginning to fail. The bracket is well known for separating from the wishbone.

[Tavan]

Just a thought - diff bush?

[griffith400]

Thanks guys,

OK, looks like I've got a few options to check. I'm not that mechanically minded but happy to have a look and see before I spend wads putting it into the garage. Guess it's out with the Axel stands again at the weekend and hope it's dry for a test drive / listen.

Thanks everyone for the ideas and suggestions. It's one of the great things about the TVR/Griff community.

Steve.

[crackedfinger]

I had the same when fitting my protechs, annoying creak that sounded like a big gate hinge. I had also fitted polly bushes and re-conned the wishbones & have S/h drop links. I drowned all moving parts with spray grease, and it worked, no more creaking. Went through whole can doing all 4 corners.

Just don;t do it just before a MOT !- watch out getting grease on the fuel line & shock piston, as the MOT tester will think you have either a fuel leak or leaking piston. I had to talk my way out of that one!

[griffith400]

Just thought I'd give a wee update for those good enough to have replied to my request for advice.

Checked and tightened just about every nut & bolt I could find under the car but nothing obviously loose. Then, as per the last post, I tried lubricating anything I could find underneath.

Good news it seems to have helped. Have taken it on a few short blasts and last night was so glorious, couldn't resist unleashing the beast when I got home after work. Again, seemed to be OK.

The bad news is I'm not sure what was the cause given I just went at everything but it's too time consuming to do a few parts at a time and then raise / check the car everytime.

Thanks for all the help as always!!!

[5.0ltr]

Ta for update. Just a thought does the car get used much/often? I find it keeps things more supple.