ATF in the transmission???

I recently purchased a British twin, the make is not material to the question. When I went to drain the transmission ATF came out, may have been in there for the 22 miles the PO put on, possibly longer, can't say.

My plan is to replace it with an regular EP gear oil, but I have never seen this situation and have no idea if the EP will mix with the ATF and can be flushed. Or, should I add some type of solvent, then the EP? Don't know. I would prefer not to pull the transmission apart, but I will if I have no alternative.

Has anyone run into this situation? What did you do?

Some modern gear oils are the same colour as ATF, that being said I see no problem at all with simply draining the existing oil and filling it with your preferred brand/grade. No flushing should be necessary, but if you want to be extra fastidious then change the oil again after a few miles of running and while it is still hot.

Redline superlite shockproof synthetic transmission oil has the look and consistency of ATF. An extremely good product. Perhaps that's what's in your new bike.

eskasteve said:

Redline superlite shockproof synthetic transmission oil has the look and consistency of ATF. An extremely good product. Perhaps that's what's in your new bike.

Click to expand...

I use the Redline V-Twin shockproof lube in my BMW R90S, it is opaque. The stuff that came out of the gearbox in question was ruby red and very translucent; I'm sure that it was ATF. BTW I spoke with a tech at Redline about the shockproof transmission oil, I wanted to know the VI numbers and if it would be compatible with the BMW's G/B before I installed it, the tech told me that it was something like 50W-250 (he told me that Redline did not have hard VI numbers) and was compatible for any application that called for one of the EP lubes.

Yes it's likely Redline. I love it because it sticks to all parts including the clutch arm cable and mechanism which rides up high above the oil level . :wink:

I've been riding Trials since 1968, and in 2010 I bought a new Gas Gas 300 Trials bike. The dealer in Central Calif. recommended ATF for the transmission. He claimed that it gave better clutch response, and allowed the gears to move more freely. I never bought into it, feeling that ATF is more of a hydraulic fluid than a lubricating fluid. However, some of the guys I ride with have been using it for 10 years now without any problems. They do change their oil every 5 or 6 rides though.

Torontonian said:

Yes it's likely Redline. I love it because it sticks to all parts including the clutch arm cable and mechanism which rides up high above the oil level . :wink:

Click to expand...

Was my hope, but it is not Redline, the fluid that came out was way too clear. Redline looks more like tomato soup, ATF looks more like Grenadine. This was, also, the same stuff the PO put in the primary chain case judging from the clarity. If he put gear oil in the primary my fun will just be starting...

tall951guy said:

I've been riding Trials since 1968, and in 2010 I bought a new Gas Gas 300 Trials bike. The dealer in Central Calif. recommended ATF for the transmission. He claimed that it gave better clutch response, and allowed the gears to move more freely. I never bought into it, feeling that ATF is more of a hydraulic fluid than a lubricating fluid. However, some of the guys I ride with have been using it for 10 years now without any problems. They do change their oil every 5 or 6 rides though.

Click to expand...

I built an '86 Fox body Mustang, Ford specified ATF in the 5 speed, manual, gear box. ATF is very popular with modern manual shift transmissions. Maybe ATF is just fine for 47 year old British motorcycle gear boxes, I don't know one way or the other (yet). My quest it to remove the ATF and hope that regular gear oil will get in where it needs to be and not be prevented from doing so because of the ATF coating. If it is as simple as adding the EP oil, running the machine and then drain (repeat x=?) I'm good. I'm hoping that someone has had this experience or has enough of a petro-chemical background to advise me.

Believe it or not, auto transmissions have gears in them, and they run fine on auto trans fluid. I run atf DXIII in my Commando. It gets into the bushes easier than the heavy 90 gear oil. I dont have problems. I also use it in my primary. No problems. A lot of manual transmissions in car and utes have ATF in their transmissions. I once bought a Ford courier ute, new. I always had problems changing gears and I told the Ford dealer to fix it. The g/box oil was removed and ATF was added instead. Never had a better gear changes prior to that.

Dereck

I have used ATF in my Norton trans for the last 100,000 miles or so.

It's also the recommended fluid in my 67 Mercedes gearbox and many over the road trucks.

What has more gears in it than a standard transmission? .....answer -an automatic transmission.

ATF is excellent gear lube and synthetic ATF makes them shift really nice. Jim

comnoz said:

I have used ATF in my Norton trans for the last 100,000 miles or so.


ATF is excellent gear lube and synthetic ATF makes them shift really nice. Jim

Click to expand...

You know I gotta ask. What brand, weight and type is it?

Guido said:

comnoz said:

I have used ATF in my Norton trans for the last 100,000 miles or so.


ATF is excellent gear lube and synthetic ATF makes them shift really nice. Jim

Click to expand...

You know I gotta ask. What brand, weight and type is it?

Click to expand...

I had to go look at the bottle.
The last time I changed it I used "Valvoline Synthetic MaxLife Multi-Vehicle Automatic Transmission Fluid" from my local CarQuest.
I have also used Mobil 1 Dexron/Mercon in the past and probably a few others.
I change it once a year -8 to 10,000 miles. Jim

Last night and this morning I did a lot of digging (Googling) on ATF and EP gear oil, some snippets of what I learned:

1) Not uncommon to mix some ATF with EP gear oil in colder climates to improve initial shifting and lubrication; ratio unclear.
2) Gear oil has significantly more zinc then ATF, it also contains sulpher.
3) The major differences between ATFs are the levels of friction modifiers, typically zinc and phosphorus.
4) The major differences between non-synthetic EP gear oils are the levels of zinc, sulpher and organic fats.
5) Synthetic lubricants gain superior properties and longevity from having their carbon chains built, rather than broken down to length by catalytic and thermal refining techniques.
6) High quality EP, organic gear oils have less sulpher. Sulpher in a high heat environment can become corrosive.
7) Synthetic gear oils have little to no sulpher.

I am fully aware that automatic transmission have plenty of gears, some planetary in arrangement. Most if not all the gears in automatic transmissions are helically cut (as they now are in automotive standard transmissions), which increases the contact area between gears lessening the load, unlike the straight cut gears in British motorcycle gear boxes and earlier automotive standard transmissions. I will say, based on what I read, I am now wondering if EP gear oil isn't major overkill; certainly the lubrication choices available 40 + years ago were considerably more limited than they are today

My plan, now, is to properly refill the transmission with a high quality EP gear oil and just forget it until I go through it. Thanks to those that responded to my question.

Heavy duty automatic transmissions still use straight cut gears. Jim

Hi All,

Strangely and bizarrely, I have just come in from the garage to have a look at this forum on the subject of `ATF"
in the primary drive. (Jim will know why - see clutch nut falls off thread!) and wow bang there is a new string about it !!!

I used to by ATF but the bottle on my shelf is actually Comma AQF and I think that ATF is/was no longer available as ATF and
the "new - correct" grade of ATF is now called AQF. I think I researched this some time ago - 1 L = 5 fills of 200 ml - so 4 fills ago!

Am I right - is AQF the new ATF ?

I have used "ATF" since the late 1970s and never had any serious wear of the transmission - just the annual clean out
due to slipping clutch at the beginning of each year.

Thanks

Staytite said:

Hi All,

Strangely and bizarrely, I have just come in from the garage to have a look at this forum on the subject of `ATF"
in the primary drive. (Jim will know why - see clutch nut falls off thread!) and wow bang there is a new string about it !!!

I used to by ATF but the bottle on my shelf is actually Comma AQF and I think that ATF is/was no longer available as ATF and
the "new - correct" grade of ATF is now called AQF. I think I researched this some time ago - 1 L = 5 fills of 200 ml - so 4 fills ago!

Am I right - is AQF the new ATF ?

I have used "ATF" since the late 1970s and never had any serious wear of the transmission - just the annual clean out
due to slipping clutch at the beginning of each year.

Thanks

Click to expand...

I had never heard of it. It seems to be a product of Comma lubricants which I have not seen in the USA.
So I don't know anything other than what google says. Jim

Hi LAB

Thanks for the link. I cannnot remember why I bought Comma AQF instead of Castrol TQF ( I think it was Castrol TQF?)
But the Comma has done 4 fills = 4 years and there is no wear or tear so I'll get another bottle.
It is mineral rather than synthetic, but I don't suppose it caused the clutch nut to fall off!

Thanks

Staytite said:

I cannnot remember why I bought Comma AQF instead of Castrol TQF ( I think it was Castrol TQF?)

Click to expand...

Comma 'AQF' and Castrol 'TQF' are probably the same spec. fluid (others may know more).

http://www.opieoils.co.uk/p-77269-castr ... fluid.aspx

I don't dick around with the gearbox as far as fancy lubes go. The best performance I get is with the dumb o Lucas 80/90. I have tried sooo many different syn lubes and none work as well as this recommended type.