oil grade question for a 5.0 mustang

[ranger99]

Hey guys, I read everyday but post seldom. My question is, I have a 94 Mustang gt, owned since new with very low milage. Manual calls for 10-30 unless extreme cold, then 5-30 is acceptable. As far as I know this engine has been back spec'd for 5-20 although I will not use it in this car. I have run amsoil every year in 10-30 but only put about 1,000 miles a summer or less on it. So, what harm would it be if any to run 5-30 in this car. Again, the manual states to run 5-30 in extreme cold only, but now spec'd for 5-20? What gives.

 

[crazyoildude]

5w20 is a great choice with some engines but that 5.0 should use 5w30

 

[ranger99]

So 10-30 is not a necessity for this engine? I have some Pennzoil Plantinum in 10-30 that I am going to use this summer. But, I have a large stash of 5-30 for my ranger but would like to use for the mustang too, the stash is large....

 

[bdcardinal]

That shouldnt have been back spec'd to 5w20. If that came into the dealer we would default to 5w30 unless otherwise requested by the customer.

 

[chubbs1]

5w30 or 10w30 really doesn't make one difference in your engine (unless it is in the MI winter). If you have a large stash of 5w30 by all means it is SAFE for your engine.

 

[Merkava_4]

You'll have a happy engine with 10W-30 MaxLife.

 

[qdeezie]

Per Ford TSB 02-1-9, you can go all the way down to 5w-20 on your Mustang. I have a 94 Mustang GT as well and I'm a 5w-30 guy. For what it's worth, I own a 1990 F150 with the 5.0 engine and I use 5w-30 in that as well. No issues with 5w-30. The only time I use 10w-30 is when I find a nice clearance sale on oil and I save it up to use during the summer months.

 

[FL_Rob]

Both are 30w oils,the 5w just has a little lower cold-pour point.
Definitely you can use 5w30 with confidence.

 

[OVERKILL]

Use a good 5w30. I assume the engine is stock?

 

[beast3300]

I would also use 5w30 in that. It is a durable engine that would probably run on canola oil.

 

[D189379]

For 1000 summer miles, any Xw30 weight will work for you.

 

[Alex38]

I wouldn't go to 5w20, but 5w30 would be about perfect if you have alot of it sitting around.

 

[Mauro]

I have an 88 5.0 LX and I've been running 5w30 Castrol GTX High Mileage for as long as I can remember. I like it due to it being on the thick side of the 30W scale. Seeing you drive your car only in the summer months, use 5w30 or 10w30.

 

[Scott88]

I use 5W-30 in my '94 for a few reasons, and I used to run 10W-30. Either way, you should be good to go.

 

[sangyup81]

It's because oil quality has come a long way since 1994. Today's 5w30 and 5w20 are way better than back then

 

[JT1]

I'd use 5w30 or even 0w30 in that engine, ford has backspec'd that engine because they too realize that motor oils have come a long way in shear resistance since that engine was originally made.

 

[Clevy]

Forget the 5w-20 spec. 5w-30 is fine. Use with confidence

 

[steve20]

another vote for 5-30.
I am in a similar situation as you: cars I enjoy, but do not drive a lot-maybe 50 miles/week each.
The Owners Manual in both my Corvettes say 5-30 or 10-30. I run 5-30 (PP)

 

[ranger99]

Thanks for all of the responses, I figured it would be fine to run 5-30, just wanted to check with the experts first. I have plenty of 5-30 pp to use up, and a few jugs in 10-30.

 

[Merkava_4]

10W-30 has LESS viscosity index improvers than 5W-30.

More base oil, less fluff.