I have a stock 2005 Verada GTVi AWD. My rear seat passengers have complained that the exhaust is quite boomy. Don't know if you'd call it a drone, but it's a fairly low frequency note.

This only tends to be a problem when climbing hills as the AT holds a higher gear (up a steep hill at 50km/h in 5th!), thus keeping engine speed low (1200rpm) and relying on engine torque to make it up the hill.

I can avoid the problem by kickdown or holding the trans at a lower gear, (say 3rd) thus bringing the revs up, but would rather the noise just was quieter!

This isn't a problem from the front seats (so I am blissfully unaware.. sounds rather good from the front actually!), only the rear seats, where it gets a bit unbearable, and not really as refined as what one expects from a Verada.

Anyone else notice the same thing? Is the GTVi AWD exhaust the same as VR/VR-X? Same as TL/KL models? I read that earlier versions of the sports exhaust did exhibit some drone, but have never ridden/driven one so can't compare.

Any suggestions or comments would be welcome. I've considered changing to an aftermarket system, but wouldn't know where to start! Plus, I sure don't want to make it any louder...

If you like the way it sounds then why change it?

Since when do we spend money on the because the backseat passengers say they dont like the way it is?

This problem ONLY occurs with the AWD models.
I have a TJII AWD sports and it is just the same.

When you are in the front you are only slightly aware that there is a "boom" coming from the back of the car.

I finally sat in the back and let the other half drive.
It really is not nice.

My suspicion is that the original development stopped too soon.
I worked for a major, good, manufacturer in the UK in a technical role.
There we had several model variants that had odd boom occurrences.
Found that the cause was 1) either the exhaust system was unbalanced or 2) that one of the body to exhaust mounting points was in the wrong longitudinal place.

1) is hard to fix as it usually means a lot of work to move mounting points sideways or rerouting the pipework and shifting mufflers so that the system hangs equally on the mounting points.

2) is easier. usually a movement of 100 mm or so away from the current position will make things much better.
I suspect that the problem on the AWD comes from the mounting point close to the rear differential.
I still havn't got round to proving this by removing the rubber temporarily from this mount.

I'll try and have a go sometime over the weekend and let everyone know the result.
Gerry

Yeah the AWD's AT decide that they are a diesel sometimes. Nothing you can really do anyways (better off kicking down anyway, its a bugger on the bottom end).

Earplugs are cheap :)

Yeah the AWD's AT decide that they are a diesel sometimes. Nothing you can really do anyways (better off kicking down anyway, its a bugger on the bottom end).

Earplugs are cheap :)

Yep, I hear ya! 50km/h in 5th is plain stupid. If only it was possible to increase the setpoint for 5th

Tell your backseat passengers to find alternative means of transport!

But yeh sounds like a problem with AWD's, only to fix it would be to get a quieter muffler installed. But like someone already mentioned, who cares lol.

its not just awd, my backseat passengers complain as well, i just turn the music up to drown out the complaining, considering sub is in the back, lol, if the dont like it they find another way, but usually they just complain. ahahaha.

mike

My sentiments exactly about the transmission 'falling asleep' and retaining 5th gear right down to 43km/h(@1150rpm in 5th!) if you're easy on the throttle. Good, so I'm not the only with the transmission that does this.

The 4 speed autos go back to 3rd at 55km/h.

Especially with the Sports/VRX muffler you do get the noise. It is quite loud as far as 'factory spec' is concerned.

Apparently the AWD's have the same gearbox as in the EVO VI -- surely an EVO is not going to troll around at 1150rpm in 5th ; Maybe there's different calibrationon our AWDs?

You have the GTVi which has a sports rear muffler on it. You could always go back to the standard AWD muffler.

I have just put a AWD sports muffler on mine and love it.

And yeah, AWD's are always noisier than the FWD's because of exhaust setup.

Yeah I think your problem is the sports muffler the gtvi has. You could downgrade but you would loose a bit of power, and it would sound lifeless + look pretty boring.

Thanks for all the responses guys.

Spud100, would really like to know what your findings are when you're done as this is something I'm quite keen to resolve. Though if the problem was apparent since the TJ2, you'd have thought Mitsu might have developed it far enough to have fixed it by the time the TW/KW was launched.

Is the muffler part on AWD and FWD models the same? I think the only difference is that the pipework takes a different path on AWD models due to the rear drivetrain, but the components (cat, muffler, etc) are shared. Can anyone confirm/correct?

i dont know about standard mufflers, although i have an upgraded exhaust system, which equals more noise, which makes me happier, which equals annoyed customers. sorry i cant help, iv got a photo of the TH front wheel drive standard muffler if need be.

I paid to get a louder exhaust. I think most people on here did. keep it, makes a sporty car's "flavour" complete:P stuff the back seat passengers. hahaha. they can shush or scat!

Nah the AWD rear mufflers are different to the FWD ones other than the pipework.
I ordered an AWD Rear sports muffler for mine and when it turned up, it was the FWD one. The mounting pins are different on the two and also i think the intake whole where the pipe goes in is in a different spot.

Thanks for correcting me on that Familywagon.

I wonder if any aftermarket mufflers would keep the same flow as the sports muffler but somehow be less boomy at low revs... I might approach a few exhaust shops. Any recommendations in the Geelong VIC area?

Thanks for correcting me on that Familywagon.

I wonder if any aftermarket mufflers would keep the same flow as the sports muffler but somehow be less boomy at low revs... I might approach a few exhaust shops. Any recommendations in the Geelong VIC area?

It's unlikely, most aftermarket mufflers are higher flowing (straight through) and would probably be louder. I'd try and find someone selling a stock awd muffler of the triflow design. You'll lose a slight amount of power but also lose a fair bit of the drone.