HT4100 4.1, 4.5, 4.9 Discussion, Ht4100 in Cadillac Engine Discussion; I am thinking of using Royal Purple 20W40 (for diesel and Gasoline Engines), in my HT4100 - 87 Eldorado. Any ...
- 06-27-07 05:05 AM #1Cadillac Owners Member
- Join Date
- Jan 2006
I am thinking of using Royal Purple 20W40 (for diesel and Gasoline Engines), in my HT4100 - 87 Eldorado.
- 06-27-07 05:56 AM #2
Stand back. Oil questions on this forum = burning match + puddle of gasoline. Lots of strong opinions.
But here goes. I'm not famiilar enough with Royal Purple to comment on it, however I can tell you this: I switched my HT-4100 '87 DeVille to Amsoil synthetic 10W-30 ASM two years ago, and send oil samples to Blackstone Laboratories for analysis at each change.
I change my oil twice a year, usually 3500 to 4 thousand mile intervals. The wear metals content is now 62% lower than the universal averages for engines of this type. I did get a small bump in aluminum and iron on the last test, but it may be because I took the sample from the filter instead of the drain stream. The TBN of the Amsoil was very high, almost new, even after 7 months in the crankcase. The oil lab has recommended I extend my drain interval to 4500 miles.
This isn't a pitch for Amsoil. I don't sell it, or cheerlead for them (at least not here). Just my experience. My point is, if you want to experiment with a product, don't be afraid - just follow Ronald Reagan's advice: Trust but verify.
- 06-27-07 12:43 PM #3
Here's the oil to which Noahsdad is referring:
AMSOIL SAE Synthetic 10w30
And this is an example of what he's learned from his used oil analysis (this one from a customer of mine with a Corvette):
Corvette C5 Used Oil Analysis Report – AMSOIL SAE Synthetic 10w30
- 06-27-07 03:50 PM #4Cadillac Owners Enthusiast
- Automobile(s): 85 Eldo Biarritz
- Join Date
- Dec 2003
- Northeast USA
Here we go again....
I recommend "Sliski 45W50". Oil manufactured from a rare Polish crude found only in a small area in the Tatra mountain range. 100% natural and organically mined. No artificial (synthetic) indgredients
- 06-28-07 02:29 AM #5
Thanks for the info. I got my answer