Oil Spec
Oil Spec
2005 FLHTCI
What oil for tranny and primary?I have 10w40 Mobil 1 Racing 4t for the primary and Mobil 1 75w-90 synthetic for the tranny?Will this work? Or what do I need?Thanks Harry
What oil for tranny and primary?I have 10w40 Mobil 1 Racing 4t for the primary and Mobil 1 75w-90 synthetic for the tranny?Will this work? Or what do I need?Thanks Harry
Extreme HDF Member
Joined: Jun 2011
Posts: 14,731
Likes: 2,536
From: Mountain Top, Alabama
Or use Mobil 1 V-Twin 20w50 Syn in all three holes.
It's made for it.
Simple, I have been using it for years.
https://mobiloil.com/en/motor-oils/m...QNWg&gclsrc=ds
It's made for it.
Simple, I have been using it for years.
https://mobiloil.com/en/motor-oils/m...QNWg&gclsrc=ds
Grand HDF Member
Joined: Jan 2012
Posts: 4,458
Likes: 2,877
From: Oklahoma
Harley recently came out with an 80W-140 lube for transmission and primary. I saw nothing on the label indicating it won't "retro-fit" into older bikes. I mention this primarily to bring up the question about why people use 70W-90 in the transmission when 75W-140 flows about as well cold and retains its viscosity better at high temperature. A caution about gear oil in the primary (not Harley's lube), the extreme pressure additives can have a bad effect on "yellow" metal (a big reason for not using it in engines) and I am not certain if the copper windings in the stator qualify as "yellow" metal.
Did your bike not have an owner's manual included? Unless you live where it is regularly quite cold, Harley recommends 20W-50 for the engine, but 10W-40 for low temperature operation. Many OWNERS have long preferred purpose made lube for each hole, engine oil in the engine, gear oil in the transmission, and primary lube in the primary. Harley is slowly coming around to agree with the owners and no longer pushing the same lube in all three holes. If you have a manual, read it. When asking for advice, you generally get "what you pay for". Everybody has their own opinion.
Did your bike not have an owner's manual included? Unless you live where it is regularly quite cold, Harley recommends 20W-50 for the engine, but 10W-40 for low temperature operation. Many OWNERS have long preferred purpose made lube for each hole, engine oil in the engine, gear oil in the transmission, and primary lube in the primary. Harley is slowly coming around to agree with the owners and no longer pushing the same lube in all three holes. If you have a manual, read it. When asking for advice, you generally get "what you pay for". Everybody has their own opinion.
Grand HDF Member
Joined: Oct 2015
Posts: 4,803
Likes: 6,917
From: Cincinnati OH.
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Seasoned HDF Member
Joined: Oct 2012
Posts: 13,097
Likes: 13,030
From: Texas, USA
Harry... Think man think. You put your physical address as your location. All you did was advertise on the internet where your 2005 FLHTCI is located. Every thief in the world thanks you.
It took me less than 10 seconds to find out your last name starts with a J and ends with an S and you live in R***land, SC. Now, if you are looking to give your bike away that's a different story.
I would send you a PM about this but you don't have enough posts.
It took me less than 10 seconds to find out your last name starts with a J and ends with an S and you live in R***land, SC. Now, if you are looking to give your bike away that's a different story.
I would send you a PM about this but you don't have enough posts.
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Cruiser
Joined: Aug 2013
Posts: 202
Likes: 71
From: Florida
Seriously....what ever oil you have handy to dump in the primary....it isn't going to matter. And ANY gear oil in the trans is going to work as well. Don't over think this...it is an antiquated v twin motorcycle engine. Change the oils and ride for Christ sake.
