1997 Mecury Gran Marquis 4.6 V-8 Oil issue

[fordman65]

Hello fellow BIOG readers.
I purchased a 97 Gran Marquis with a 4.6 V-8,it has 225k on the motor. Bought it from my mechanic. I just took a long trip (round trip about 1k). I had the oil changed right before the trip at a local Firestone. They put in 5w-20 Kendall Semi-Synthic. I asked them to put that in,due to no knowledge of how the previous owner ran the car. thought being run some thin flush the gunk out. Mechanic advised me to run 10W30.
Just checked oil today and only after a week from the oil change down a quart.
I would not be as concerned if I was closer to 4k-5k miles. But only after 1k ?
Is that normal for the 4.6 V-8's ?
Read a few things on the web stating that these motors can burn oil.
Any ideas or suggestions?

Thank you.

 

[SatinSilver]

Highway miles can burn oil at a faster rate. I'd top off with some High Mileage oil. Maybe even change the pcv valve.

 

[Nick1994]

I agree with SatinSilver

Although, did you check the oil after they changed it? Maybe they didn't even top it off.

 

[Pontual]

Why do you think the mechanic said 10w30? He knew it was a burner.

 

[fordman65]

He recommended the 10W-30, due to the possible wear from the mileage. Wear between piston rings and cylinder walls.

 

[fordman65]

I am not a huge fan of high mileage oils. Sometimes the HMO mask the true problem.

 

[Merkava_4]

Originally Posted By: fordman65
Mechanic advised me to run 10W30.


That's a smart mechanic. He probably has good common sense too.

 

[Delta]

Weren't those still spec'd for a Xw30 in 1997? Either way, after 225K, 1qt every 1k is not bad at all.

 

[shiny]

Originally Posted By: Delta
Weren't those still spec'd for a Xw30 in 1997?

Yes.

 

[CT8]

Run 10w-30.

 

[fordman65]

He is an awesome mechanic. He used to run a Ford Service department, before the dealership went out of business. He can tear a Ford motor apart in his sleep.

 

[fordman65]

It was specd for 5W-30. I will probably switch to Castrol 10W-30 maybe the 5W-40 Full Synthetic.

 

[Ethan1]

Originally Posted By: fordman65
I am not a huge fan of high mileage oils. Sometimes the HMO mask the true problem.


That's the point

 

[buck91]

Sometimes those 4.6s will suffer poor vale stem seals, even after the design was "fixed" in 96.

 

[tig1]

My 96 GM 4.6 had 218 K when sold. I used M1 10-30 and it used a qt. every 6500 miles from start to finish when sold.

 

[FastLane]

I use 5W30 in my 4.6. It uses no oil between oil changes. Still on the full line.

 

[Blinker]

Didn't these engines suffer from a valve guide seal defect?

 

[Blinker]

After reading thru the comments I see someone mentioned it as well. I dont know what year the issue was corrected but I do know they had a defect design

 

[Branson304]

I would use Valvoline MaxLife or Pennzoil High Mileage, 5W-30 winter/10W-30 rest of the year. This engine definitely has some miles on it so I'm not surprised at the consumption & you shouldn't be either, especially on a thin 5W-20.

 

[TFB1]

Originally Posted By: Ethan1
Originally Posted By: fordman65
I am not a huge fan of high mileage oils. Sometimes the HMO mask the true problem.


That's the point

Exactly...

And if the consumption is reduced why should you care???

I'm using M1 HM in my '98 4.6, has cut consumption in half... Was using a quart in 2.5K mi, now in range of qt in 5K mi... It's setting on ½ qt low but I added a half qt at around 3.7K mi just before a couple road trips...