Engine amsoil...

amsoil...

Just got my order of Amsoil 5W-30 full synth. in today. After refilling and starting the engine, I did notice that the engine was much smoother - maybe in my head, but could swear it has a much smoother idle.

Oil pressure isn't MUCH different, but seems to be more stable. Instead of 50psi, I'm running around 53psi @ 3000rpms and max psi beforehand on the Mobil1 was around 65psi @ 4000rpms-redline....now my gauge says 71psi 4000-redline.

It was actually kind of funny...when merging onto the interstate, I always redline 1st, redline 2nd, then hold 3rd until I'm merged into traffic. When accelerating in 2nd and 3rd, I could actually watch the oil pressure DROP as the rpms climbed higher. I'd start @ 75, and by the end of 2nd it would be @ 70psi, then by the end of 3rd, I'd be @ 65psi. With the Amsoil, it holds 71psi and doesn't drop like with the Mobil 1.

Of course, I'm just waiting for a really hot day to see what kind of heat resistance this stuff has....but so far, so good.

Trav

Very interesting... Did the Mobil1's pressure tend to drop much after a few thousand miles? The Amsoil is in fact highly resistant to volatility and is quite stable. It is great at absorbing carbon, gas, acids and such, keeping the engine clean, so it's good to stick to the recommended change intervals. I change it every 5000 miles. I switched to Amsoil at 2200 miles... Now at 40000 miles, the oil level doesn't go down between changes, and I'm running extensive N/A mods and redline it often. I use Amsoil in my engine, tranny and power steering and get better performance and fuel economy too.

Actually, with the Mobil 1, the pressure remained the same throughout the oil's life - 5000mi change interval.

As far as I can tell, the 2 culprits are heat and rpms. 30 minutes on the highway @ 70mph and I'd be running 50-55psi @ 3000rpms. Drop it to 3rd and make a hard run to 80 or 85 and the pressure would fall to 45psi @ 3000 and after about 5 minutes of calm driving, would slowly come back up to 50psi. And if ambient temp is high (85ºF and up) then the oil pressure would sit at 45-50psi @ 3000 - I've seen it go as low as 40psi @ 3000rpms and that is scary. It's not a good thing when oil pressure is FALLING as the rpms are RISING - kinda bass ackwards, there.

Think a Amsoils manual transaxle fluid is a good idea? I know GL-4 is less corrosive to the synchros with the lower content of EP additives and GL-5 provides better EP protection....which should I choose, ya think??

Trav

SAE 75W-90 GL-4 or GL-5 is recommended as stated in owner's manual... Amsoil's Severe Gear GL-5 https://www.amsoil.com/storefront/svg.aspx is MT-1 approved and recommended where a GL-4 is called for. GL-5 provides extra protection, although a GL-4 or, to a greater extent, GL-5 lubricants can, if not properly formulated, become corrosive to yellow metals if the lubricant temperature exceeds 250 degrees F. The API recently came out with a new specification to address this possibility; 'MT-1'. Amsoil synthetic gear lubes all meet this spec, therefore do not attack yellow metals. Amsoil will run cooler, reducing the possible high temperature situation, and meet MT-1, therefore will not attack yellow metal even if the temperature does climb to this extremely high 250 degree mark.
Amsoil's SEVERE GEAR 75W-90's copper corrosion testing per ASTM D130 shows a value of 1b after 3 hours at 121 °C (250°F). The scale goes from 1 (a,b or c) through 4 (a, b, or c). 1a means there is no effect of the lubricant on copper. 1b is the second best possible result.
I have full confidence in it. Now at 40000 miles on it, it still shifts better than ever.

Amsoil