Need some help ! Burnt grease smell on wifes car ???

My wife has a 2002 Mitsubitshi Montero with 68,000 miles . She loves that car and refuses to part with it .

It has a odor of burnt grease every once in a while when she shuts it off after driving .
I am thinking a alxe boot ???? Does that make sense?

Does not burn engine oil or leak on the ground anywhere , so I don't think it is coming from the engine . I can't seem to find where its coming from . It does not smell like engine oil. It reminds me of burnt grease .

Do you guys have any ideas ??
I going to do a timing belt change and want to fix whatever this smell is from at the same time .

Could be a transaxle leak? Have you pulled the stick on the trans and looked at the color of the fluid and smelled it?

You say it's not leaking onto the ground, but a valve cover can leak ever so lightly onto the exhaust manifold. The reason she may not smell it until she stops the car is because the airflow under the hood, while driving, carries the odor underneath the car and out the back.

I wouldn't think an axle boot would smell. Not hot enough there. I may be wrong though.


Or....have you been sitting in the car lately?

Al with that kind of Mileage on it I,d be more apt to look for brake wear & OR wheel Brg,s then CV joints , But either one of those could cause a cv Boot to start leaking due to the grease posablly boiling out .

Should be Fairlly easy to tell by laying Yer hand on the center of the outside of the wheel & see if anyones hotter then the others . Other then that I,d think of a Leaky cam cover Gskt posablly seaping onto the intake or exhaust manifold . It,ll burn off before leaking on the ground normally . Best of luck , Bob

Trakternut said:

Could be a transaxle leak? Have you pulled the stick on the trans and looked at the color of the fluid and smelled it?

You say it's not leaking onto the ground, but a valve cover can leak ever so lightly onto the exhaust manifold. The reason she may not smell it until she stops the car is because the airflow under the hood, while driving, carries the odor underneath the car and out the back.

I wouldn't think an axle boot would smell. Not hot enough there. I may be wrong though.


Or....have you been sitting in the car lately?

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Its driving me crazy ? I just don't think its a engine problem . No valve cover leaks that I can find . Motor is clean as a whistle. To me it smells like grease . Not like tranny fluid or engine oil or power steering fluid .So far I've checked all the oils and can't find a damn thing wrong or low ,but even I can smell it at times .
Every time I smell it, it seems like I am in my good cloths and by the time I go in and change and come back out to work on it ,the smell is gone .

Cowboy said:

Al with that kind of Mileage on it I,d be more apt to look for brake wear & OR wheel Brg,s then CV joints , But either one of those could cause a cv Boot to start leaking due to the grease posablly boiling out .

Should be Fairlly easy to tell by laying Yer hand on the center of the outside of the wheel & see if anyones hotter then the others . Other then that I,d think of a Leaky cam cover Gskt posablly seaping onto the intake or exhaust manifold . It,ll burn off before leaking on the ground normally . Best of luck , Bob

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I checked the brakes and they are good . I said Boots in my first post but I was thinking CVjoints too .

Happen to have a mudflap (or anything else) close to an exhaust pipe eh ........?

Big Dog said:

Happen to have a mudflap (or anything else) close to an exhaust pipe eh ........?

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Nope ! Thing is the car runs great . No front end noise you would usually hear if a joint was failing .

I am about to give up . I thought maybe the engine cam seal was leaking but that seems ok and I have no oil loss .
I am running out of places to look

The only time I,ve had a grease smell like that was due to the front wheel Brg,s on My wifes PT cruiser . There wasn,t any noise either . But I could sure feel the heat when touching the wheel & jacked it up to find out it did have more play in it then it should have causing it to overheat . Not saying thats it , But the only thing I can think of .

Sounds like You,ve eliminated perty much everything else . Good luck.

It's from all those In-N-Out Burger wrappers you have been stashing under the front seat.

Cowboy said:

The only time I,ve had a grease smell like that was due to the front wheel Brg,s on My wifes PT cruiser . There wasn,t any noise either . But I could sure feel the heat when touching the wheel & jacked it up to find out it did have more play in it then it should have causing it to overheat . Not saying thats it , But the only thing I can think of .

Sounds like You,ve eliminated perty much everything else . Good luck.

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Thanks Cowpoke ,

I'll take it for a spin and take another look at those wheels . Thanks again

DaveNay said:

It's from all those In-N-Out Burger wrappers you have been stashing under the front seat.

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Those things are nasty !!! Had one about 10-15 years ago and swore I would never have another . Tasted like a piece of card board .

Uhhh....Al, they WERE cardboard!

Look for a heat shield on the cat getting too close to some under body sealant. Can give off a lot of odor and never show a burnt spot.

Well I think it is either the fragulator or a mufler bearing.

check and see if it's tape, insulation, or a piece of plastic getting to close to the manifold - I had this in my 85 GMC recently when the plastic wire guide broke and got too close to the heat.

waybomb said:

Well I think it is either the fragulator or a mufler bearing.

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Just installed a new one .Old one was the wrong color and you know what that means .....

Erik said:

check and see if it's tape, insulation, or a piece of plastic getting to close to the manifold - I had this in my 85 GMC recently when the plastic wire guide broke and got too close to the heat.

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I am going to put it on the lift and just let it idle to see if I can find anything . Its a great little car and we would like to take it down to the daughters for a few days visit . I just don't trust it until I find out whats going on .

Might be a better idea to take it out for a drive prior to putting it on the lift. Seems to me that this is as likely to be a rolling problem as an engine problem.

jimbo said:

Might be a better idea to take it out for a drive prior to putting it on the lift. Seems to me that this is as likely to be a rolling problem as an engine problem.

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Yes ,I should have added I planned to do that too . Thanks !!

Maybe a belt driven accessorry is going south. Or maybe the automatic tensioner for that belt. Look at the belt for unusual wear/melting. If apparent, then I'd start narrowing down which driven accessory is failing.

Ok ??? The wife just told me she heard a hissing sound the first time she smelled the burnt odor and a guy at the gas station told her it was the CV BOOT . Does that sound logical????? If ithe CV joint built enough heat to hiss you would think I would hear something when i drive it ?????

Its a easy fix to change out the whole alxe assembly but I want to make sure that is my problem .


Ideas or comments on this ????

easy enough to put the car on your lift and check the boots for damage.
if one is damaged, pull it back to see if there is excessive wear of the CV joint visible - or if there a zerk, add some HD/moly grease and see if that makes the burnt smell go away or get worse.

Throw it on the hoist and inspect the half-shafts. A bad boot will be obvious.

Does this vehicle have boots on the front driveshaft? On the slide coupling for instance. That may be an issue around the exhaust...

The CV boot isn't the only problem. If in fact the smell is coming from the boot, then the boot may have failed allowing the grease for the CV jopint to escape. The CV joint is tearing itself apart for lack of grease. Thus, the heat build up and smell. Just get a complete reman half-shaft and replace the thing if that's it. Simply replacing the boot will not help anything.

If she heard the hiss while in her car, I don't think it would be the cv joint. But stranger things happen!

The CV Boot should have no tears holes or cracks. Usually, you'll see a line of grease around the shaft at the failure, on body and suspension parts. If it does, replace the half shaft.

If the CV joint is failing, every time the car is driven for any length of time, it should get hot and smell. Get a floor jack ready along with a jack stand and a tire wedge. Drive the car a few miles, shove the tire chock in, jack it up, get that jack stand in there so we don't here about Al being beheaded, and put your hand near the CV joints. You should not feel heat coming off of them. Don't touch them hot - your fingers will be burned if you touch a hot one.

Alls good info here , But I dont see the sence in replacing anything that there is nothing wrong with , At least untill its Inspected . If the cv joints are not loose & just the boots are bad , the boots can be replaced easilly enough & the cv joints repacked with grease .

You can put a brand new shaft in & It more then likelly wont solve your problem , If the sizzling is coming from the outer CV joint I,ll stand by what I said all along the Outer wheel Bearing is probablly bad & causing the heat & the grease to boil out of the outer CV joint .

If left go long enough , not only the CV joint will need to be replaced but the entire steering knuckle , hub & brg assemblly will have to be replaced . It is a sealed bearing that presses onto the hub & into the knuckle itself . Even with the Proper tools & presses its not allways easy to do or cheap .

If the bearing housing has spun inside the knuckle at all , It is shot & will not except a new bearing properlly , I,ve learnt this the hardway . It is a flaw in the design on a lot of different front wheel drive types of vehicles in the earlly 2000,s .

You need to jack up the vehicle from the body points behind the front tires allowing both wheels & axles to hang freelly , taking the preasure off of everything . You should be able to feel the rough bearing as well as play to determine if its 1 or both sides . In my experience its more times then not the drivers side that has the most problems .

I Appologize for my lack of grammer & spelling & not trying to come off as an expert . but I,ve been through it several times on many different makes & models , only after paying to suposedlly having it fixed right by a reputable shop . Every time They replaced the bearing & full shaft . But never caught the fact the Hub & knuckle was causing the real problem . It was an expensive lesson at MY cost untill I decided to Finally do it Myself . Once again best of luck . Bob

I think I just found the problem . I don't like doing my own oil changes on the Montero. So since it was due for a oil change ,I took it down to the local lube shop and ask them to look for a oil leak and inspect the axle boots while they had it on the rack changing the oil. It appears it is comming from the rear cam seal . Its not much and my oil level never varies between changes .
The book says theres a access plug with orings where the Cam is inserted from the rear of the block on the 3.5-6cyl engine and these orings should be changed every once in a while as needed .
Sounds like a pretty simple repair ,,,,,hopefully .... On another note has anyone ever used the Bars Oil Leak fluid to recondition seals ? I am wondering if I should add it to the oil ????

I think i'll change it when I do the timing belt next week .
Thanks for the replies !
Allen