2001 Isuzu Trooper 3.5L DOHC Motor...................... Burns approximately a 1 quart of motor oil every 3-400 miles. 10/30 Motor Oil. Whats the problem? 2nd question: Same vehicle, Torque on Demand 4WD system.... There is a flashing warning light on the display... Transfer case is full of fluid and box on front differential is full of oil. What does this mean?

Question edited for clarity.

5 Quarts with Filter change.

1999 Isuzu RODEO recommended synthetic oil and filter

https://www.searchforparts.com > oil-change > isuzu-19...
With filter 5 quarts After refill check oil level. ASLQT-EA Signature Series 5W-30 Synthetic Motor Oil ASLQT-EA

How much oil capacity in a 1999 Isuzu Rodeo? - Answers

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Jan 3, 2012 - Q: How much oil capacity in a 1999 Isuzu Rodeo? Write your answer... Submit. Related questions ...

1999 Rodeo oil change ' Bob Is The Oil Guy

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Feb 13, 2013 - ...This is the 3.2 V6 engine ran from 1998 to 2002. I think after 2002 a new V6 engine was used I'm not sure. This particular Isuzu 3.2L DOHC ...

10w-30 is what you would use in winter and 10w-40 in the summer

A "leak down" test will test the cylinder effectiveness, as will a compression test. These will tell you how good the engine is.

1996 Isuzu Truck Trooper 3.2L MFI SOHC 6cyl
The Engine Oil Capacity 5 7/10 Quarts (including filter)

Engine Oil Type and Weight
Oil for use in temperatures ranging from -13 to 100 degrees
5
Application:
Oil for use in temperatures ranging from -13 to 100 degrees
Note :
Quarts without filter change

Oil for use in temperatures ranging from 32 to 100 degrees
5
Application:
Oil for use in temperatures ranging from 32 to 100 degrees
Note :
Quarts without filter change

VALHD30
Application:
Oil for use in temperatures ranging from 32 to 100 degrees
Note :
Valvoline Premium Conventional 30 Motor Oil


Hope this help (remember rated and comment this). Good luck.

How much is a little oil? 1 quart(US) in 5000 miles is reasonable oil consumption. If you don't have any major leaks, the oil is going out the exhaust pipe. As the engine wears the piston rings dont seal as well as they used too and the oil gets burned in the combustion process. You didnt mention how many miles you have on the vehicle, An engine with 150,000-175,000 is going to burn a little oil..

Check your oil, does it look like chocolate milk, if so you have blown a head gasket. Or you could just have a bad valve cover gasket, this allows oil to drain down onto the exhaust where it burns and as a result, white smoke. If you get enough of it, when you pull your plugs it will coat them in oil.

Classic Trooper problem. You can get a lot of quiet(er) troublefree miles out of your Trooper with religious, regular oil changes. Isuzu is now advising the use of Mobil 1 0w30 synthetic motor oil, changed at 5000 mi intervals to quiet the lifter tapping that you're experiencing. If you're a DIYer, you can pick up 5qt jugs of this oil at Walmart for $23-$26. -Or, you can buy the basic oil change and provide your own Mobil 1 0w30 to the tech to keep the costs down.

It'll take 150-300 miles for the noise to settle down after the fresh oil change. Keep a close eye on your oil dipstick. As soon as you're coming close to a quart low, top it back up. The 3.2l motor will start tapping again when the oil level drops or is near the time to change. Forget the advice about the belt tensioner needing to be replaced. That is rarely the source of the noise. I have two Troopers, Christophe. They're the ones that aren't tapping like crazy at the traffic light. Enjoy your Troop. -Geoff

600 perquart miles is a piston ring sealing issue, U don't say the miles on the car, but it is rings.

Yep it's more than likely worn valve stem seals. What happens when your motor cools down the seals contract and oil passes through the gap and then when you start it again the oil burns. It will more than likely last years depending on how much oil your burning if you need to put more than 500ml in a week you probably should get a mechanic to check it out.