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Several have totally missed the point. It's not just motor oil! It is a man made synthetic that is formulated to be used in all the "holes" .
Been using it for over 25K miles now.
I don't see shavings on my drain plug. But, I been running mine for 15K before the MoCo said it was ok to do so. So, I'm only on my 2nd fill of Syn3 in my tranny!
[sm=chairshot.gif][sm=boink3.gif][sm=icon_beat.gif] C'mon get that Synful MOTOR OIL out of your trans and get your mind right with Redline Shockproof Heavy........I did and my wife likes me again now plus I have 37% fewer cavaties
Several have totally missed the point. It's not just motor oil! It is a man made synthetic that is formulated to be used in all the "holes" .
Been using it for over 25K miles now.
I don't see shavings on my drain plug. But, I been running mine for 15K before the MoCo said it was ok to do so. So, I'm only on my 2nd fill of Syn3 in my tranny!
Syn 3 is a Group 3 synthetic oil, meaning its made from crude oil outta the ground. It's considered synthetic 'cause Mobil lost a court case with Castrol, IIRC.
Syn 3 ain't a bad oil, there are just others that are better, and cost less to boot. The HD hype tends to tick me off. [8D]
Per your comments here, what do you see as the difficulty (if any) with Formula+ in the primary and tranny? From information I've gathered, both on this forum and others, Formula+ is straight 50 wt with additives (don't know which ones). Poll results show an almost even usage of SYN3 and Mobil 1, but I lean toward H-D but have had no problems in my car, track, or tractor with Mobil1 inc. their filters. Appreciate any comments you have. Sincere thanks.
OneBlackFly (aka Paul)
ORIGINAL: pococj
ORIGINAL: OneBlackFly
Poll results show an almost even split between SYN3 and Mobil 1 75W90. But when I change next, in goes Mobil 1 75W90 to tranny. Motor oil just is too light for gears.
Motor oil and gear oil viscosity are measured using different methods. The 75w-90 gear oil is equivalent in viscosity to 10w-50 to 20w-50 motor oil.
10w thru mid range of 20w engine oil = 75w gear oil
Mid 20w thru mid 30w engine oil = 80w gear oil
Mid 30w thru low 40w engine oil = 85w gear oil
Low 40w thru 50w engine oil = 90w gear oil
60w up motor oil = 140w gear oil
Gear oil usually has additives, sulfur being one of 'em, that do good things with gears. Sulfur in a motor ain't a good thing. I don't know what the drawbacks to the new Formula+ stuff are, or what compromises are made to allow its use in both tranny & primary. I run ATF in my primary, and pretty much have for over 20 years when I had a primary chain. But I like belt drives and no oil even better!
Several have totally missed the point. It's not just motor oil! It is a man made synthetic that is formulated to be used in all the "holes" .
Been using it for over 25K miles now.
I don't see shavings on my drain plug. But, I been running mine for 15K before the MoCo said it was ok to do so. So, I'm only on my 2nd fill of Syn3 in my tranny!
i just went to the redline heavy, did about 150 mi this weekend, and i do without a doubt feel a diff, and hear a diff in the shifting.
much much smoother. time will tell.
i just went to the redline heavy, did about 150 mi this weekend, and i do without a doubt feel a diff, and hear a diff in the shifting.
much much smoother. time will tell.
I put syn 3 in all holes at the 1000 mile change. The trans has more noise coming out of it. And the intermesh changing gears is not right. I am droping the syn3 and putting in Mobile 75/90.
I put syn 3 in all holes at the 1000 mile change. The trans has more noise coming out of it. And the intermesh changing gears is not right. I am droping the syn3 and putting in Mobile 75/90.
Good idea, you will never go back to the 20w50 in the trans after you try the gear oil. The redline shockproof heavy works well too. I am using that with excellent results.
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did 250 hard miles last Sunday... got home and checked the tranny which HAD Syn3 in it... it was so thin i couldn't see it on the dipstick. the other day i dumped the Syn3 out to put in Mobil 1 75/90 and the Syn3 in the drain pan looked like metal flake paint.
after another hard 250 miles yesterday with Mobil1... Neutral is real easy to find and can feel a distinct firmness when it goes into gear. plus it seemed to eliminate some of the "clanky" sound the tranny had.
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