80w 90 gear lube instead of HY Gaurd

[buickanddeere]

Why would you install the wrong oil with the incorrect additive packages ? Sae gear oil is not wet clutch and wet brake compatible. GL-5 will attack clutch and brake fibers. If any moisture enters the system GL-5 will also attack copper allow components.
Do you know how much repairs cost ?
You could fill it with diesel fuel and it would operate for a while. Just because it "works" doesn't make it right.

 

[jbwilson]

Hoping to help the discussion by attaching a link to a chart comparing the different oil viscosity standards. It seems that using the centistoke basis of measurement, Hy-Gard is a lot more fluid at 100C (9.4 cst) than 80W - 90 gear oil (20+ cst). However at 40C both oils are around 50 cst. I need to add that I don't much about lubricants and so whether or not Mr Dylan needs to replace his transmission oil.

http://media.noria.com/sites/archive_images/Backup_200107_viscosity_table_2.gif

John

 

[California]

I like this solution: Drain the 80-90, reinstall the used Hy-Gard that came out and run for a while to flush the system, (but don't install the dregs at the bottom of your drain can!) then replace with all new Hy-Gard. By that time the proportion of additives from the 80-90 remaining should be very slight. And replace the hydraulic filters.

 

[dylan 413]

i understand this it was a mistake dont worry i havent used the tractor much since the change and im going to get hy gard this weekend and a new filter to get all the gear oil out

 

[dylan 413]

update- I warmed up the tractor and drained the oil, took the filter off put a new one on and got all the oil off the metal screen (no metal luckly) i added some amalie all trac 245 hydraulic trans oil (cheap flush oil) and i made shure it met specs, witch it does on the back i says meets jd20b specs. now im gonna get some hy gard over the weekend and another fresh filter and do the final fill. Thanks for all the help guys glad i caught the mistake before a real problem happend.:thumbsup:

 

[ray66v]

Hyguard and 80/90 gear oil are WAY different. It's probably okay now, but it may over pressure stuff and plain not flow in the winter. Transmission oil is about 5 to 10w oil vs. 80/90w gear oil. Ralph

Both the hydraulic transmission oil, and the 80-90w gear lube are approximately the same viscosity.

The transmission oil, is gear lube, that's why they are interchangeable, in a differential.

Hydraulic transmission oil is approximately 30w, and the 80-90w gear lube would be around 30w on the engine oil scale. However, the scale for gear lube is a different one, creating the misconception that it is heavier. It is not.

Viscosity does vary slightly from brand to brand. But, if you do a side by side pour test, of trans oil, and 80-90w, you can see it for yourself.

One TBN member actually did a timed viscosity test, after we discussed this. Because it is hard for some to accept.

 

[MHarryE]

Buickdeere got it right - viscosity is not the important thing - it is the EP additives in the gear oil that are not compatible with parts in the transmission. Example - Kubota allows either their hydraulic oil or 80W-90 in their front axle but only hydraulic oil in their hydro.

 

[fortec]

I disagree with brown40. It needs a double flush with the correct fluid to be reasonably ok. Consider it an expensive lesson learned and remember that lubricants are not as expensive as machinery.

 

[Fawken]

thanks for the help ive only use the tractor a little since the oil is in there and the funny thing is the hydros work fine

It might seem fine but as mentioned it is not good for the pump and will cause grief especially when it gets colder outside. At that point you'll be putting even more strain on the pump and gumming up seals and valves.

 

[fortec]

Further to what you have said Fawken I would also be concerned about compatibility with seals since the gear oil chemistry will certainly be quite different to that of Hy-Gard.