Anyone use 10w40 or 20w50?

Status
Not open for further replies.
Originally Posted By: turtlevette
For me the heavier oils are a problem solver. My 79 trans am leaks out of the rear main like crazy with 5w oils specifically M1 tdt. Straight 30, 15w-40s and 20w-50s don't leak a drop.

Exactly.
 
I run 5 or 15/40 in the diesel truck, 10/40 and 20/50 in the bikes. Most places dont stock the 20/50 non motorcycle oil anymore, even 10/40 is harder to find where I am anyway.
 
I run semi-synthetic 10W-40 (API SN, ACEA A3/B4) in my car all the time. It's in there right now.

There were problems with mineral 10W-40 using cheap VIIs in the old days. These gummed up the engine. But a Euro spec ACEA oil needs to pass a stay in grade shear stability test, so they should use higher quality VIIs and be much better than the old 10W-40 mineral oils that gave this grade it's bad rep.

As for 20W-50, I ran this in my old air cooled motorcycles, GTX 20W-50 was the go to bike oil back in the day (in Oz). I found it sheared out too quickly in my shared sump bikes, so I switched to Penrite HPR 30, a mineral 20W-60 popular as a affordable road and track oil back then. Suddenly no more problems with the oil shearing out. I suspect Penrite also used high quality VIIs in their HPR mineral series of oils. They sold them as performance oils and they seemed to live up to their name.
 
I used Kendall GT-1 High Performance 20w-50 conventional for years in my 1987 Alfa (2.0L DOHC). The last two years I've used Rotella 15w-40 with little difference in my oil pressure.
 
Originally Posted By: Joe90_guy
Quite a lot of the Middle East, Africa, Asia and Latin America uses 20W50 because it's one of the cheapest oils you can physically make.

Not so long ago, 10W40 semi-synthetic was the predominant grade in much of Europe.

It's interesting to note that Imperial Oil (our Exxon-Mobil) no longer makes any 40 or 50 grade PCMOs except for the motorcycle specific stuff and a couple other specialties. You simply won't find a 10w-40 or 20w-50 from them. Castrol, on the other hand, has no problem with those offerings, plus monogrades.
wink.gif
 
Always have run 15W-50 in Our Shop Truck: a 2002 Ford Ranger,4.0L SOHC. Which is one of the years with the Chronic timing chain/tensionor/Guide issues....that puts so many of these trucks and Explorers in the graveyard with the Death Rattle before their time..... Im nearing 160,000 miles with ZERO issues....Best Engine I have ever owned. Could It be the heavy oil??? Im convinced.
 
Ive used 20w50, straight 40 for ages, up to 2006. When I first fill the car with 10w40, it looked watery for me. Now Im on 5w30 watery oil. 20w50 is fluid when you compare with straight 40. It goes, glup, glup, glup, glup ... not blop, blop, blop

Ow that was scientific! Kkkk
 
Friend has a 90 Cherokee that had some pretty bad oil leaks. Temporarily, we put 20w-50 as the 10w-40 leaked out in it to stop it leaking so bad for an off road trip.

Didn't help all that much (but was cheap!!!), but man, those lifters were NOT happy! It quieted down after a few hours on the trail. But was noisy again the next morning.

Now that, literally every, seal has been replaced, it's running a more appropriate oil grade.
 
After a 100,000 miles on my company Ford Ranger V-6 I switched it up to 15W-40 Delo400. It ran on to 258,000 when it went up for auction and still ran fine, passed SMOG tests (ODB-II), and was a decent truck.

All my over 100K cars and trucks either GET HDEO's or Maxlife 10W-40 ...

The Harley and the Honda XL350 get 20W-50 and always have.
 
I switched to AMSOIL XL 10w-40 in my Subaru Tribeca as the engine used too much oil with 5w-30. The thicker viscosity of the 10w-40 essentially cut my oil consumption in half. The engine was noticeably quieter with the 10w-40 and I didn't notice any increase in fuel consumption with the heavier oil either.
 
Originally Posted By: ShotGun429
Always have run 15W-50 in Our Shop Truck: a 2002 Ford Ranger,4.0L SOHC. Which is one of the years with the Chronic timing chain/tensionor/Guide issues....that puts so many of these trucks and Explorers in the graveyard with the Death Rattle before their time..... Im nearing 160,000 miles with ZERO issues....Best Engine I have ever owned. Could It be the heavy oil??? Im convinced.
160,000 miles is hardly any mile at all. I've hardly ever heard of an engine problem on cars with 160k or less miles unless it's a GM intake manifold issue or a sludged up Chrysler 2.7L V6.
 
Not all 10w40s should be painted with the same brush. Depending on the ambient, a synthetic CJ-4/SM 10w40 would make a better winter engine oil than 0w40 or 5w40. The attraction would be more shear stable and higher HTHS.

Unless high oil pressure was my objective, I would pick a mono-grade SAE40 over 20W50 and an SAE 30 instead of 10W40. The mono-grades would not shear permanently or temporarily in use.

The old 10w40 and 20w50 engine oils were known for their viscosity loss as measured in a uoa, but how much more viscosity was lost (%TVL) during operation is a mystery.
 
Originally Posted By: car51
Garak: that's interesting info, so thank you
smile.gif


I've seen PYB in monogrades recently. GTX certainly has monogrades and 10w-40 and 20w-50. Wakefield Canada does not let the grass grow under its feet. If someone will buy a grade, they will sell it, and if they sell it, they will ensure it is on the shelf everywhere. For example, you can get GC at just about any place that ever sells Castrol up here.
 
That gives me an idea Garak. I have 3 liters of 10w40 Castrol motorcycle oil. I'll buy a couple more and put them in a Toyota that calls for 5w20 and test it after 14,000 km.
 
I run 10w40 in my Peugeot 106 and 20w50 in my 1975 Ford Capri , before I used to run 10w40 in both, a few months ago i learned that I should run 20w50 in my Capri and that is what they ran on from new, since i put 20w50 in it the engine runs so much smoother, quieter and it also burns about half of the oil it used to...., no change in fuel economy or responsiveness / power
 
Last edited:
Status
Not open for further replies.

Similar threads

S
  • Locked
Has GTL proved itself?
2 3
Replies
51
Views
2K
dnewton3
M
Castrol edge extended gold bottle questions
Replies
17
Views
1K
tired
O
  • Question Question
Death Valley Drive Using Thin Oil
2 3 4
Replies
64
Views
3K
edyvw
B
PUP or VRP
2 3
Replies
46
Views
3K
JimPghPA
53' Stude
Anyone still use Mobil Super 5k?
Replies
15
Views
539
burbguy82
Back
Top Bottom