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  • Fox 5.0 Mustang Tech

Let's talk Oil and etc....

  • Thread starter Thread starter KFRG
  • Start date Start date Apr 10, 2008
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KFRG

New Member
Jan 6, 2004
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#1
  • Apr 10, 2008
  • #1
Hey Guys, bought a 5.0 with just over 60K on her. Owner states the car has been running conventional oil. I know many here run synthetic oil's such as M1 etc.
I also know the potential of leaks the synth oil can cause.
Basically, what I am asking is the switch to synthetic worth it, and what are the benefits of doing so if I already change my conventional oil often (no more than 3K, the car will be a weekend driver). I honestly do not want to have to deal with oil leaks at all.
If I stay conventional, what is the best grade (weight) and brand out there for our cars (I live in the Northeast)? I am sure the preferred grade/weight has changed over the years than what it states on the oil fill cap. I also take it a NAPA or Motorcraft filter is best?
Coolant: Any preferred brand you guys use?
Rear-diff: I have heard of guys using everything from synthetic oil to ATF, what is the best stuff to fill the rear up with?
Anything else I should change besides the spark plugs and wires?

Thanks alot guys.
 
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KFRG

New Member
Jan 6, 2004
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Apr 10, 2008
#2
  • Apr 10, 2008
  • #2
Agh, newb mistake guys mabye this should have been started in Tech. Sorry guys.
 

bloopbloob

Member
Sep 27, 2006
578
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Alberta
Apr 10, 2008
#3
  • Apr 10, 2008
  • #3
people have argued about this forever in previous posts. i'll just state what i use and that i'm happiest with it over other things i have had before. if you don't have oil leaks now, i wouldn't worry about oil leaks with switching to synthetics...

5-30 synthetic motor oil, whatever major brand is on sale (worth it)
royal purple synthetic in the diff (worth it)
regular atf in the tranny, it didn't seem to like the synthetic stuff (not worth it)


thats just me though. may not really help much at all, or any, but an extra couple bucks for something that could make it perform better, or last longer is def. worth it in my opinion. i'd also get an air filter you can clean also (k&n?). coolant is coolant if you ask me. all just ethylene glycol, unless they came up with some new additive or something.... haven't bought it for a while.
 

5.0 Nostalgia

10 Year Member
Feb 28, 2003
904
5
39
CT
Apr 10, 2008
#4
  • Apr 10, 2008
  • #4
I would stick with the conventional oil. When I bought my 91 GT almost 7 years ago, it had about 55,000 on it. I started off using Penzoil and a Fram filter, then switched to Castrol GTX 10w-30 and a Motorcraft filter. My dad owns the car now, but I still do the maintenance for him and use the same parts. I contemplated switching to synthetic as well, but never did and don' t plan to. I don't think this is an apples to apples comparison, but I used Mobil 1 on the stock motor on my 89 LX. It burned oil, but also had 100,000 miles on it and a GT-40 intake (known for sucking oil through the PCV and into the runners).

I just use the regular Prestone coolant.

I would leave the rear diff fluid alone.

If you still have the original plugs and wires, you probably want to change them. If the wires are original and have the year on them, save them. The Ford Racing wires are fine for replacements, as well as Autolite plugs. I forgot the gap out so somebody will have to help out here, but I think it's .048 or .053.
 

Roland69

Sergeant Tangnet
Sep 17, 2005
2,867
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Port Elgin, Ontario
Apr 10, 2008
#5
  • Apr 10, 2008
  • #5
I use castrol GTX 10W-30 and a NAPA gold filter.
 

LaserSVT

Got FB banned again for saying nards
Founding Member
Nov 29, 1999
9,390
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Apr 10, 2008
#6
  • Apr 10, 2008
  • #6
I always use Valvoline Synthetic blend 5w30 and ONLY Motorcraft oil filter. IDK about the Foxes but for mod engines it has a check valve that keeps the oil form completly draining into the pan
 

85_SS_302_Coupe

it sucks (I know) to be on the receiving end
15 Year Member
Nov 11, 2003
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Apr 10, 2008
#7
  • Apr 10, 2008
  • #7
I'm a big fan of Valvoline Maxlife. I've been using it for 4 years in my Mustang and i beat the hell out of it on a regular basis and it's got over 250k on it so i would say it's doing something good.
 

grey5.0beast

Cookies should never be DUNKED!!!
Aug 3, 2004
0
1
0
atl ga
Apr 11, 2008
#8
  • Apr 11, 2008
  • #8
I have been using castrol gtx 10w30 my car's whole life and it seemed pretty damn good, but with the new build I am running some crap 5w30 for break in oil then switching to castrol syntec blend in 5w30.
 

Grn92LX

Fidanza Man!
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Jan 14, 2001
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Apr 11, 2008
#9
  • Apr 11, 2008
  • #9
You can get 5qt jugs of mobil 1 10w30 @ walmart for just over 20 bucks. Though its not a true class 4 synthetic, its still better than regular oil. Not saying regular oil is bad, unless the manufacturer specifically says the engine needs synthetic.
 
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KFRG

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Jan 6, 2004
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Apr 11, 2008
#10
  • Apr 11, 2008
  • #10
Thanks for the replies guys. I think I will just stick with conventional for now. Grn92LX, you live in NY as well, do you run 10W30? Just trying to gauge the best grade to use as it seems poeple run a variety on the forum, I guess depending on climate location.
Also, a real stupid question, these cars take 87 right? Assuming since these are not high comp. engines.

Thanks again guys, I pick the car up tommorow.
 

Grn92LX

Fidanza Man!
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Apr 11, 2008
#11
  • Apr 11, 2008
  • #11
I just picked up a 5 quart jug of Mobil 1 10W30 @ walmart for $22. 10W30 or 10W40 is fine. I'd go 10W40 now for the warmer months if you can. Mobil 1 doesn't make it in 10W40.

You can run 87 no problem and you should be ok running it with slightly bumped timing. None of my cars run on 87
 
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KFRG

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Jan 6, 2004
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Apr 11, 2008
#12
  • Apr 11, 2008
  • #12
Thanks man. I wonder if Motorcraft or Castrol makes a 10W40, i'll have to check that out. Mabye during the winter a 5W30 would be a good choice.
Yeah, the car is basically stock minus gears, headers, and exhaust so 87 should be fine.
 

85_SS_302_Coupe

it sucks (I know) to be on the receiving end
15 Year Member
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Apr 11, 2008
#13
  • Apr 11, 2008
  • #13
I would run synthetic on a freshly rebuilt engine with new rings, but on a 100k+ engine i'd stick with conventional, maybe a blend. Then again, i run strictly Mobile 1 synthetic in the Merkur but being a turbo engine i want extra protection since the oil also supplies the turbo and it has to stand up to extreme heat.
 

strtrcr50

New Member
Jun 21, 2006
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Previously from Dirty Jerzey exit 7a
Apr 11, 2008
#14
  • Apr 11, 2008
  • #14
I run amsoil.
 

Grn92LX

Fidanza Man!
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Apr 11, 2008
#15
  • Apr 11, 2008
  • #15
KFRG said:
Thanks man. I wonder if Motorcraft or Castrol makes a 10W40, i'll have to check that out. Mabye during the winter a 5W30 would be a good choice.
Yeah, the car is basically stock minus gears, headers, and exhaust so 87 should be fine.
Click to expand...

If you were going to run different weights for summer and winter i'd do: 10w30 winter and 10w40 summer. Either one all year round is fine though.

I run the mobil 1 in my Audi 1.8T engine like 85_SS mentioned above about turbo cars and heat.
 
U

UnderdogGN

New Member
May 7, 2006
74
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0
Apr 11, 2008
#16
  • Apr 11, 2008
  • #16
I actually run Rotella T diesel oil in mine. Its 15-40, and has extra additives in it.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,224
17,909
224
Massachusetts
Apr 11, 2008
#17
  • Apr 11, 2008
  • #17
Castrol GTX and Motorcraft FL-1A here.


I'm not a big synthetic oil fan. In fact, it's sometimes not recommended in manual transmissions because it makes it too slick and the synchros can't grab the gears and slow them down. I know Tremec now states to run conventional ATF in it's 3650 because of that exact reason.
 

vikingpower

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Dec 6, 2004
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Apr 11, 2008
#18
  • Apr 11, 2008
  • #18
I would recommend changing the diff fluid, but its a nasty job.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
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Apr 11, 2008
#19
  • Apr 11, 2008
  • #19
Any approved oil will be fine. I also have been switching over to HDEO's as the conventional stuff loses all its ingredients.

Run the least viscous oil that maintains decent pressure at all times.

As others stated, I like synthetics for extreme climates or extended OCI's. Something like a zero-weight-synthetic could be nice on a fresher mill in the winter, but otherwise you're probably ok.

FWIW, the Motorcraft oil is very good stuff (the lighter weights are blends) and it's priced pretty decently.

Good luck.
 

Shakerhood

20+ Year Stangneter
Oct 28, 2004
3,356
208
114
Ohio
Apr 12, 2008
#20
  • Apr 12, 2008
  • #20
I just started using the Blended Synthetic in my Mustang as it sits for extended intervals. My Lifters have never liked 5W-30, so I just stick with 10W-30 and a FL1-A Filter!
 
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