Question about 1999 GMC Suburban

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Bad Smell only when window is down...Smells like propane

I had full service done, Radiator,brake,engine,transmission and rear axle gear box oils replaced. 54,000 miles Was told everything looked good. Days later I was on the road for 2 hrs with ac running pulling boat and was about to clime hill so we turned off ac and rolled front windows down. A propane type smell hit us. Could not figure out smell and it would not go away. Only smell it when we are moving. Only smell it when window is down and we are moving. I brought it back to Chevy dealer and they said they think the rear axle gear box got very hot and created the smell and was released through the breathing tube. They think the gear box is going out.They replaced oil again. Was told once more the oil had no metal shaving and it looked good. My question; How hot can oil get before it starts to smell. Is it possible the gear box is going out...Or Help

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  • Barefooth2o Aug 17, 2008

    The rear differential is the gear box I am talking about. They said they did a test on the cat. and exhaust system and it checked out OK!



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No the ring and pinion seems ok from what you are wouldn't smell it up front while moving do to wind and what not,
oil can smell at low temps.
you may have an exhaust leak at an O2 sensor seal. or something relative to that.

Posted on Aug 17, 2008


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I have a leak coming from the drivers side of my engine of coolant its coming out of a hole above the trans any idea what that hole is or what goes there

hi Kemal.
  1. Park your vehicle overnight on a clean patch of pavement or a large, clean piece of white paper.Either tape some sheets of paper together or buy a roll of plain white commercial wrapping paper. Newspaper is too absorbent and can change the color of the stains.
  2. Place marks on the paper.
    Show where each of the four wheels is resting, and indicate the front and rear ends of the vehicle.
  3. In the morning, move the vehicle and look for small puddles or traces of liquid on the ground or paper.
    Touch and smell each puddle or trace of liquid.
Here's how to decipher the evidence:
  • If it's clear, watery, and under the air conditioner: It's probably normal condensation if you've used the air conditioner recently.
  • If it's black or dark brown, greasy, and located under the engine area:It's probably oil. Figure out which part of the vehicle was over the spot. Look under the hood around the oil filter and the engine and under the vehicle for leaks around the oil drain plug, the crankcase, and the oil pan below it.
  • If it's thick, black or tan oily liquid: Gear oil may be leaking from a manual transmission, the differential, an axle, or the steering gears. Any of these leaks needs immediate attention.
  • If it's red, pink, or reddish-brown and greasy and you have an automatic transmission: It's probably transmission fluid. Check the transmission dipstick, and if the level is low, top it off with the proper transmission fluid. Then check the dipstick again in a day or two. If it's low again, have a professional check the transmission to make sure that the seals are intact.
  • If it's watery or slippery; green, red, blue, or yellow; and is coming from under the radiator or engine: It's probably coolant. Check the radiator, pressure cap, engine, and hoses for leaks.
  • If it's oily; pink, red, or clear; and you find it toward the front bumper (usually on the driver's side): It's probably power-steering fluid. The power-steering system is sealed and shouldn't lose fluid. If it's a light-colored or clear fluid: It may be brake fluid. Even if the leaks have dried, the stains should be visible. Leaky brakes are too dangerous to leave unattended. Have a professional repair any brake fluid leaks immediately.
  • If it smells like rotten eggs: It's battery acid. Avoid getting it on your hands or clothes and have the battery replaced.
  • If it smells like gasoline: It probably is! If the smell is coming from under the hood, check around the fuel pump and the fuel injectors - or the carburetor if your vehicle has one. If the leak seems to be under the center of the vehicle, check the fuel lines. If it's under the rear end, check the fuel tank.

Dec 14, 2017 | Cars & Trucks

1 Answer

I just bought a 2005 Jeep Liberty and there is a leak under the front end after sitting for a few hours. It's clear and blace in a few spots. They have checked it and all fluid levels are full and can

is car 4WD?
ok, is this your first car?
is this your first car with A/C? for first time ever using and A/C?
(btw front defrost mode uses A/C functions)

if pure water, its just A/C condesate, 100% normal all cars.
today cars have a wide variaty of new fangled fluids.
in the olden days we had tan, and green'
now its many.
toxic AF (antifreeze) green, pin, yellow, red, orange , etc. now.
Engine oil think goodness is just tan/brown or black
pull dip stick gander at the tip (THAT is your color today)
now the transmission, A./T automatic, it usually is pink, but can be
read or dark red. (if your year has a dip stick on A/t pull it and bingo your color is there)
then there is the leaking, (rare) window washers. (can be any color)
but is soaping to the touch.
last is M/t boxes. manual gear boxes,, and transfer case (4wd)
the they can be , clear to brown. my synthetic is clear but is very viscous, and smells sweat.
Some axles and transmissions have (gear boxes) have hypoid gear lube that is brown and stinks to high heaven.. nasty smell.
But this too can be different today, and be any color, from clear to purple to brown.
last is brake fluid, its always clear, but in large volume or old is amber.
it smells sweet. and sticky.
that is what we have today.

find your cars A/C condensate drip tube under car
and memorize that location, then when it leaks, you know.
its that.
on some cars its at passegers toes.
on my jeep its dead center, of car.

Mar 29, 2014 | 2005 Jeep Liberty Sport

1 Answer

Theres a smell of gear oil in the cab when driving.What could it be?

(1) motor oil only smells when its being burned.
(2) the output of the air ducts is in front of the gear shift area.
So, I'm thinking that you have an oil leak in the engine compartment (which may be dripping onto the exhaust system), and the oil has found a hot part of the engine/exhaust, and the smell of heated oil is wafting through the cabin air filter into the passenger compartment through the air ducts in the middle of the dash to just above the gear shift area.
If my theory is correct, you should be able to re-route the burned oil odor by changing the setting of your air ducts by changing the setting from its current setting to a "defrost-type" setting, wherein air entering the passenger compartment comes from the ducts below the windshield, rather then entering through the openings at the center of the console.
Ultimately, your fix will be to locate and resolve the oil leak.

Here's your list of possible culprits for the 1997 Nissan Pathfinder

Priority Action Part Type Cause
1 Inspect - Valve Cover Gasket -- Valve Cover Gasket Leaking Oil.
2 Inspect - Oil Filler Cap -- Oil Filler Cap Damaged or Missing.
3 Inspect - PCV Valve -- Plugged or Damaged PCV Valve.
4 Inspect - Oil Pan Gasket -- Leaking Oil Pan Gasket.
5 Inspect - Head Gasket -- Leaking Head Gasket.
6 Inspect - Oil Pump - divided O-ring or Oil Pump Gasket

If the odor really is gear oil (aka transmission fluid) and not motor oil, then there's a leak coming from the automatic transmission/manual transaxle.
Look under the transmission after the car has been parked awhile, and look for a reddish oil spot/blot/pool. transmission fluid is dyed red just for the purpose of differentiation from other automotive lubricants. You can assist the process of color differentiation by putting newspaper under the vehicle once it's been parked for the night.
Placing enough newspaper may also keep your Pathfinder from depositing a nearly-impossible-to-remove oil stain onto your garage floor overnight.
If you already have an oil stain on the floor, try a spray can of engine degreaser first. Citrus degreaser next.

Oct 20, 2011 | 1997 Nissan Pathfinder

1 Answer

Mazda 323 auto gear box when engine up to running temp and been driving for about 15 mins it keeps wanting to change gear culminating in the hold light flashing...and lumpy when slowing down or speeding...

You need a full service of the auto transmission. Check the oil condition for burnt smell.
The oil may be burnt out and fails to lubricate when temperature goes up.
But most likely the gear gaskets or gear teeth are worn out.

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1 Answer

Transmission slipping when you first accelerate. Wondering if it could be something electrical. Please advise on what needs to be done.

you have an electrical gear box but it still works on oil presher and clutch/brake bands,,,if there slipping first check the gearbox oil is full and the colour of it,,it shouldbe red,,if its a dark brown and smells burnt you need to have the gearbox looked at,, do this sooner than later as the longer the box slips the more its going to cost you fixing it,,

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1 Answer

Signs of transmission problems

The most reliable and tried and true method is to check the transmission oil. Check it for...
1. Correct level
2. Right colour: a nice light red. (or somtimes yellow) not brown
3. Smell, it should have a not unpleasant smell, if it smells 'bad', it is starting to break down and will attack the friction material on clutch packs and brake bands.
4. Remove the transmission oil pan and check it for flecks of friction material, metal filings and pieces of rubber.
If any of these things are present, you have, or will soon have a transmission failure. The whine could be the transmission oil pump, the gear set is known to to come incontact with the pump body causing whining noises and creating metal filings which cause the transmission valves to stick..

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Rear direrintial

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if its manual sounds like your clutch could be slipping does car smell of burt clutch?
check cluth adjustment
may need new clutch
do stall test with hand brake on, foot (heel-toe) on brake and accel pedal to about 2000rpm then let out clutch and car should stall if engine revs go down and engine still runs but you can rev causing slip and you will now smell what slipping burnt clutch is replace it.

if its auto check trans oil level and what does it look like red-good
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