75/90 or 75/140 in '14 RK Tranny?
Ultimate HDF Member
Joined: Jun 2009
Posts: 6,899
Likes: 3,412
From: OH
They did not specify which seals were failing. I can ask when i stop up there tomorrow. I think the real heavyweight lubes gained popularity in 09 with the 5th gear whine issue. I do believe in using gear lube in the transmission but i think 75/90 is plenty stout.
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Tourer
Joined: Apr 2006
Posts: 440
Likes: 13
QC - Thanks for the reply. Good to know you're not having any issues with the Valvoline 75/140 in the tranny. I'm going to use it this season. I don't anticipate problems but it's good to hear someone has used it.
Ultimate HDF Member
Joined: May 2008
Posts: 7,439
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From: 'Noke, VA
I have noticed that the 140 doesn't work as well in the winter, so for a while there I changed it out seasonally. One year I forgot and left the 90 in over the summer and never noticed any difference in the heat. So I stick with 75/90 now (Mobil 1, if anyone cares).
Seasoned HDF Member
Joined: Mar 2009
Posts: 24,682
Likes: 9,162
From: Snow Hill, NC
I think 140 wt is a bit too thick, I saw somewhere that 75w90 was a bit better, flows a little easier....this is what I use. Just dumped it when I did my motor swap, I had like 7000 miles or so on it and was still clear... ItS Walmart full syn
Road Captain
Joined: Jun 2013
Posts: 631
Likes: 17
From: Finger Lakes NY
***Never mind, I just looked and the shock proof is 75/90...still pours like sludge though.***
Hard to believe 140 is too heavy when people have had such good luck redline shock proof in the tranny. The red line flows like molasses.
Maybe they had seal problems tough long term...?
Hard to believe 140 is too heavy when people have had such good luck redline shock proof in the tranny. The red line flows like molasses.
Maybe they had seal problems tough long term...?
Last edited by zeke383; Jun 9, 2016 at 06:52 AM.
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Seasoned HDF Member
Joined: Mar 2009
Posts: 24,682
Likes: 9,162
From: Snow Hill, NC
140 weight probably works fine, I prefer 90 wt. I am pretty sure they will both protect well I just ride in the winter a lot and the 140 wt felt a bit thick during the cold months.