Transmission Whine?????

[Mathew26]

I'm sorry I used the term foam. That was incorrect of me as I was trying to keep this simple. The truth is GL1 non EP is thick and sticky which basically allows it to climb up to the gears above the fill level of the transmssion. Now as per Fiat and as per rebuilding many transmissions GL1 that goes in your transmission should be SAE 90 non EP, which means 75W or 80W/90 is in fact not correct. I want everyone to know I don't care where or from who you get your GL1, but I want your transmission to last for years to come. And on a side note if you trully think 10W-40 or 20W-50 is an adequite replacement fo GL1 then its your car use it in your car. But first do me a favor and take 1 quart of GL1 and 1 quart of 20W-50 take off their caps and pour them at the same time into 2 different buckets, and see which one emptys first.

[pope]

My friend Matt,
That would be true is nothing else matters but the pour test. Things do not work that ways though. The pour test is not a test because multi-weight oils have been altered in the lab by adding plasticizers to the oil to make it flow better in cold weather.
That is why the straight 90 weight still pours slower than a multi grade oil. What benefits the multigrade oils give you is better shifting at cold temps. As a multi-grade heats up, the plastic molecules change shape and viscosity changes to the latter number. They get thicker. Your test should be to pour a quart of each "hot" at operating temp and you will see that they pour at the same rate.
A 75W90 gear oil becomes a 90 at temp., but coats the gears better until it heats up. Oil engineers figured this out a long time ago. I'll bet you use a multi grade oil in you engine instead of a straight weight, same principle.

[So Cal Mark]

I got the motor oil suggestion directly from chemical engineers at Mobil Oil, Castrol and Royal Purple. I addressed this subject with them over the past year and they all agreed this was a more than acceptable solution to the lack of availability of GL-1

[Mathew26]

Pope, the main thing I was trying to address was the comments on 10W-40, 15W-40, and 20W-50 being the “correct viscosity to said gear oil (which is mineral oil).”

Oils meeting the SAE's low temperature requirements have a "W" after the viscosity rating (example: 10W), and oils that meet the high ratings have no letter (example SAE 30). An oil is rated for viscosity by heating it to a specified temperature, and then allowing it to flow out of a specifically sized hole. Its viscosity rating is determined by the length of time it takes to flow out of the hole. If it flows quickly, it gets a low rating. If it flows slowly, it gets a high rating. No way does a 20-50 have the viscosity of a 90 weight. Maybe a 50W but definately not a 10W-40 or 20W-50 as specified in the Haynes Manual. 90 weight is 90 weight not 50.

Also as Pope said there is no shortage of True GL1. If there was I would not have 40 gallons sitting in the warehouse.

[red107]

Also as Pope said there is no shortage of True GL1. If there was I would not have 40 gallons sitting in the warehouse.

I agree I went to napa two days ago and they had 20 or so gallons of GL1 So I bought a few.

[courtenay]

Gotta tell you - I just changed the synthetic stuff a PO had put in my car with Vick's GL1 and it seems to make a difference to the way the car feels shifting and running. Way better!

[pope]

Matt,
I want you to take this in the good spirit I am dispensing it. I am saying this with good love and joy to you. That said,...

You are confused about oils. The numbers on gear oils and motor oils are not the same. They are not calculated the same. There is no correlation to each other. Only products in the same category can be compared. A 90 weight gear oil cross-references the same as a 40-50 weight motor oil. (same thickness at temp).

The "W" in multigrade oils stands for WINTER. That means the first number is the viscosity of that oil at 20°. As the oil heats up, the grade changes to the last number. It therefore serves two purposes.

YES, a 10W-40 or 20-50 does have the same viscosity as a 90 weight gear oil at temperature, as does a 75W-90. Temperature: means hot in the gear box or engine.
A 20W-50 and a straight 50 are exactly the same viscosity at temperature. The multigrade has the advantage of changing its viscosity according to temperature.

I know that just by looking at quart bottles in your hand, most people would come to the same conclusion as you, but you have to understand that science is at work here.

Good Luck

[pope]

Bruce, since we do not know what the previous owner put in, its not fair to compare. Cant go wrong with GL-1, but previous owners are the biggest problem.

[Mathew26]

Pope, I do get the humor in this debate. And with this I will let it die on the note that TRUE SAE GL1 non EP is out there to be had. Also, that as per FIAT the transmissions need GL1 90 SAE non EP, and that this doesn't include 75W90 or 80W90. I state as just simple fact from FIAT for other to see and know.

[So Cal Mark]

I agree that many of us can easily get GL-1. But I've learned from numerous threads on this forum, owners that live in semi-rural areas have trouble getting ahold of GL-1. 10/40 motor oil is a more than adequate substitute for those owners

[johnssi]

Ok, Ok, so here is the $64,000 question... which oil do I use in my trans? It sure sounds like the GL-1. Where can this be had.. at Vick's Auto? Great discussion though, I've really enjoyed this thread.

John

[ga.spyder]

I suffered(financially) through a tranny rebuild.The mechanic had me look at the inside ,which was a gunky mess!I dont know what the p/o had put in there,but it did my tranny no good.I am not willing to experiment with anything other than the GL-I.It is always available from Vicks,it is what Fiat recomends,and it is way cheaper than a new or rebuilt tranny!Trust me!! The other alternatives may or may not be fine...I will let someone else find out.
Craig

[johnssi]

Thanks Craig. I just checked the trans fluid through the filler plug. When I pulled the plug out to check the level, fluid started slowly dripping out. It came out the consistency of cold maple syrup and only a slightly lighter color than that, but foamy to be sure. I had only moved the car in and out of the garage to get more space on the side, so it was relatively cold to start with. I am now guessing that the PO must have used the foaming oil. I guess the best thing to do at this point would be to I service the transmission, ie: fluid and filter. Anybody have any other suggestions? An could this be the cause of the whine? Remember that's where this thread started!

[So Cal Mark]

foam is a bad thing, and if the level is full you may be on the cusp of bearing failure. Changing the fluid is the first step, and the cheapest

[pope]

per FIAT the transmissions need GL1 90 SAE non EP, and that this doesn't include 75W90 or 80W90. I state as just simple fact from FIAT for other to see and know.

I will let the Fiat Factory Shop Manual speak the simple fact for itself.