SHO Motor Oil? - 1991 MTX

[Lurch]

The manual says to use 5W-30 or 10W-30 API-SG Service type oil. Now, at my local Wal-Mart, there were many brands of oil, both synthetic and straight up petroleum-based, but no API-SG, they were all like SJ, CF, SL, etc., no SG. My question is whether these are ok. And I would like to know what type motor oil you guys use in your SHOs.

PS I can't wait to get mine back from the shop, it is getting new clutch, new flywheel, and new rear main seal. I want my SHO back!

 

[fricker66]

A quick search function on the forum should yield plenty of opinions/results on which oil is recommended for the SHO. I believe Castrol GTX is the most highly praised oil from the users of this forum. The grade of multi-weight is very dependant on the climate in which you live. I'd recommend only using the 5w-30 when/if the temperature falls below the ambient degree as mentioned in the manual. Otherwise, 10w-30 should be fine for most driving conditions.

From my own experience, the best protection is regular, timely oil changes with a quality filter. Hope you enjoy getting the SHO back on the road!

 

[93MTXSHO]

If you look on the back, at least on Havoline motor oil, it says one API classification, and then underneath or somewhere on the back, it says something like: also satisfies.........

 

[DavidT]

Hey Lurch,
Welcome to the forum thumbs_u
What year and color is your sho?
I live in Knoxville too
Where are you located?

 

[NWGRN94MTX]

It's ok it run a high grade oil. The Grade "SG" was the top spec. back in 1991, 11 years later, the spec is up to "SJ". Just use the SJ. I would use the same brand and type as the previous owner.
IMHO if it was broke in with Dino, use Dino. If it was broke in with Syn. use Syn. If it's ran 5w-30, keep using 5w-30, If it was using 10w-30 use 10w-30. Just be sure to use a quality oil filter. I use either Mobil 1 filters or K&N filters.

Have fun.

 

[shojuan]

You can't go wrong using the forum favorite: Castrol GTX. Or maybe Castrol GTX high-mileage formula if you've got lots of miles. Use 10W/30 unless the weather is cold as a witch's *** in a brass bra. Then use 5W/30. How cold does it get in your parts during winter time?

BTW, the API ratings are backwards compatible. The current rating is SL which is backwards compatible with SG. In general the higher the rating the more improved the oil. BUT the difference between SL and SJ standards is that SL has a lower concentration of anti-wear additives in an attempt to prolong the life of catalytic converters. That doesn't mean that a manufacturer hasn't made other improvements in their SL rated oils. But it's something to keep in mind if you want to use a good SJ oil and are concerned that it's not SL.

FWIW I use Redline synthetic 10W/30 in mine right now. It's SJ rated and redline doesn't intend to change that. I also use an oversize Mobil 1 MI-301 oil filter. Same price as the standard size MI-209 filter and fits an MTX perfectly. A tight fit in an ATX I've heard though. Really expensive oil and a very expensive filter. Not many will want to spend that much on the oil ($8 a qt! eek! ) but the $10-$11 for the filter is a worthwhile purchase if you can afford it. If you can't then just stick with the $2.77 Motorcraft FL-400S or FL1A (oversize) at walmart.

Hope this helps

Rick

 

[jthomas68]

It`s been said that 5W30 is used for the break in period on the new motor,but it ahould be switched to 10W30 after that.

 

[sdpatt]

266,780 miles on Castrol GTX 10W-30. It never gets below 0 degrees F here in Dallas so I haven't considered using the 5W-30. Questions?