Just thought you might like to hear a real road test under somewhat warm conditions here in Az.

Last week in 115 deg F weather at cruise speeds with Mobil 1 V twin oil, Mobil 1 in the tranny and syn III in the clutch (didn't swap the clutch oil), I would regularly see 230-255F on the engine oil temp at cruise of 75-80mph after about 1 hour of driving. Usually stayed at 230F. I do have an HD oil cooler, it kicks in at about 195F (oil temps hold at 195 for about 10 minutes, then it slowly increases as whole motor heat soaks.)

I thought I would try Amsoil, so after a 500 mile breakin of a new cam, I had the guys swap all the holes to Amsoil. I just finished that ride a few minutes ago, and after cooling off in the pool, heres the numbers and impressions.

Still 115 degrees ambient, still cruising at 75-80 for about an hour, results in exactly the same temps in the motor; 230-255F. I could not hear or feel any difference in motor or tranny while driving or shifting.

Overall, I could see no difference between Mobil 1 and Amsoil, which is good.

I do however note a huge difference from when I used Dyno/Syn III and now the synthetic mobil/amsoil. It's cooler, it's quiter, it shifts smoothly. Just my opinion, I may be wrong.

Going back to pool...

 

Both of those oils are so similar (both GroupIV synthetics) that I would always go with the least expensive because both are top shelf synthetic lubricants.

 

Agreed. I tired Amsoil casue my indie had it, I needed a change so walla. But next time, unless the autozone down the street carrys it, I'll be back to Mobil 1 v twin. Simple, cheaper.

 

So .. which Mobil 1 in the primary? 20W50, 10W40, or something else? Thanks.

(on another note - tried SYN3 in the engine and it now runs hotter and noisier than w/ Red Line 20W50 - back to Red Line soon)

 

20/50 in the primary.

 

UPDATE, tranny is obviously harder to shift. With Mobil 1, it was smooth in all gears, could even get a green like neutral from 2nd, not even close with the AMSOIL, it's shifting notchy and taking a few taps/wacks to get into gear. Going back to Mobil 1 gear oil this week.

 

So you like the mobil v twin and the mobile gear oil better..right?/ What wgt was the gear oil your running? I am currently running Mobile V Twin and Mobile 75W90 in the tranny and I really like it so far..thanks for the up date

[IMG]local://upfiles/33788/648443EB88444FA9B72DDA6778EA31BB.jpg[/IMG]

 

Regarding the Mobil 1 gear oil, is there any advantage/benefit of the 75W140 over the 75W90, or vice versa? Thanks.

(btw - I know there is a cost difference between these two gear oils, but I'm asking about performance)

 

I'm running 85w140 (not Mobil 1) in my tranny to quell some of the clattering and whining typical of the '07 6-speed, but you should be fine with a 75w90 in your 5-speed. I ran 75w90 in my old RK for 106k miles and never had a lick of trouble with the tranny, or anything else for that matter.