Took my sis's 3.0v6 TF for a spin. Noticed some engine noise at around 3000-4000rpm rev range when driving. Sounded very "growly" behind the fire wall, almost like main engine bearing noise. Noticed it is quieter when you start it up after it is cool, then gets progressively louder as it warms.

Here is the funny part, free rev the engine at 3000-4000rpm and it sounds fine in the engine bay although exhaust seems louder for some reason. Even at higher revs, doesn't seem to be any knocks in the engine or than usual magna intake noise. Its had 15,000 km oil changes, and no sludge in the engine. I never heard of any main engine bearing failure in the 3.0 or 3.5 third engines, but are any documented or recalls for such a problem?

A friend says it could be an exhaust crack causing this. Spoke to an exhaust shop who said that it is not uncommon for engine pipes to crack on 3rd gen v6s which could cause these abnormal sounds. That true?? Getting my brother in law to take it down there and checked out.

Any ideas before I send him down the wrong track?

Does the sound disappear when you push the clutch in? I'm assuming that's what you mean by free revving.
If it does, it is gear box related. I have this problem with mine and the Transmission guy said it is the input shaft bearings. There are 2 tapered roller bearings. Be prepared for round $1000 to get it fixed :(
Mine is booked in for tomorrow.

No, its an auto.

Does the sound disappear when you push the clutch in? I'm assuming that's what you mean by free revving.
If it does, it is gear box related. I have this problem with mine and the Transmission guy said it is the input shaft bearings. There are 2 tapered roller bearings. Be prepared for round $1000 to get it fixed :(
Mine is booked in for tomorrow.


ouch man!

to the first post - id def try exhaust first

Does the sound disappear when you push the clutch in? I'm assuming that's what you mean by free revving.
If it does, it is gear box related. I have this problem with mine and the Transmission guy said it is the input shaft bearings. There are 2 tapered roller bearings. Be prepared for round $1000 to get it fixed :(
Mine is booked in for tomorrow.

$1000 ?
where are these roller bearings supposed to be?

$1000 ?
where are these roller bearings supposed to be?

On the input shaft in the gear box. There in with zillions of cogs. Other than that its hard to describe as Im not a mechanic :P

ok cool
oh i suppose all the labour is the main cost...

Labour is about $700

I had the exact same thing with my auto. When you mentioned everything in your first post, i was saying to myself "yep, i had the exact same thing".

Now i converted to manual, and its gone. Its not from your engine, it comes from the gearbox, or clutch assembly i would say. Not the exhaust

Ive done an engine bearing in a te. It sounded fine under acceleration but when i backed off thats when you could hear it. Not a sound i want to hear again.