Synthetic lubricant for transmission?

[Bolt]

Please post up your experience with any synthetic lubricant you may have used within the standard transmission and has shown a drastic improvement . Please post up weight and brands. I want to hear about pure synthetics only. No blends. I am especially interested in hearing if the classic problem of shifting from first to second when the transmission is hot. Does this improve and by how much? Or is synthetic lubricant overrated for Standard transmissions in these Vipers.

Bolt

 

[96GTS]

I put in Amsoil and I've had no problems. If you're reluctant about switching, do as Mother Mopar says and follow what's in the owner's/shop manual.

 

[Bolt]

I put in Amsoil and I've had no problems. If you're reluctant about switching, do as Mother Mopar says and follow what's in the owner's/shop manual.

I did change the fluid with the OEM stuff and shifting still ***** when the trans gets hot. I was thinking of trying Royal Purple. With Slick 50.

 

[Steve 00RT/10]

I've used Amsoil for 30 years in many vehicles with excellent results. Probably close to a million miles. I put Amsoil in the Viper tranny a little over 40,000 miles ago. Replaced it with 32,000 miles on it this past spring. This lube had 5-6 track events, about 15-1/4 mile passes, and at least 25 autocrosses on it. Oil analysis showed it to be in very good shape and easily capable of longer life.

As for observations: Shifting is extremely smooth with absolutely no 1-2 problems hot. (of course I don't recall any problems with the OEM fluid on the 1-2 shift prior to changing) The short throw MGW shifter is cooler than it was with the Castrol in hot temps. In fact, after also changing the rear end to Amsoil 30,000 miles ago, I think the water temp dropped a couple needles worth. I will test this theory again when I swap out all the OEM fluids next week in the new 2001 GTS/ACR we just bought. The cars are pretty much identical drivetrain wise except the 2000 car has a 3:45 Unitrax rear end and the 2001 car has a stock rear end with a 19" wheel package---effectively dropping the rear end ratio to 2:92. The new one is definitely running hotter than the 00, although not abnormal. It's now between the 2-3 bars at freeway speeds and 70 degrees or so. The 2000 car was about the same but dropped to well below the first bar under the same driving conditions. If anything the 3:45 gears would contribute more heat to the equation

Steve

 

[Bolt]

I'll search for Amsoil in the area. I'm game I'll try anything at this point. I'll report back if it helps. You sold me in it.

 

[Bolt]

Update:

I contacted Diamler Chrystler and I have a good friend who works in the development of these Vipers. He put me in contact with an engineer who works on the drive train from the crankshaft back. So this guy knows these transmissions well.

In 1998 Dodge viper changed the fluid in the transmission from ATF to Gear lube. This engineer said there is absolutely no differences in the transmission to accommodate this thicker lube. The reason for the change was that they were getting complaints of transmission noise in neutral. The gears where making noise with the thin viscosity ATF. The fix for this was to go to synthetic gear lube made my Castrol. Castrol manufactures the Mopar synthetic lubricant for these transmissions. This engineer gave me the part number of this lubricant. $18.00 per qt. They do not recommend any other gear lube. Not even Royal Purple. This man gave me examples of transmissions which came back and the results of using alternative lubricants. I put the Mopar lube in my transmission.

Results so far: I see no difference in shifting and 1st to 2nd occasionally sticks after the transmission warms up just like before. This Saturday is the real test. I’ll be drag racing and I’ll report back how it did and if I see any improvements. Maybe over time it will work itself into all the areas.

Bolt

 

[Racer Robbie]

QUOTE":
This engineer gave me the part number of this lubricant. $18.00 per qt. They do not recommend any other gear lube. Not even Royal Purple. This man gave me examples of transmissions which came back and the results of using alternative lubricants. I put the Mopar lube in my transmission.

Results so far: I see no difference in shifting and 1st to 2nd occasionally sticks after the transmission warms up just like before. This Saturday is the real test. I’ll be drag racing and I’ll report back how it did and if I see any improvements. Maybe over time it will work itself into all the areas.

Bolt
-----------------------------------------------------------
I have been using royal purple for the last three years and have had zero problems. I put it in at 3500 miles and now have 15,100 miles on the car. The transmission is quiteier, cooler running, and easier to shift. In no way am I putting down what DC says as I am sure they know more than me. I also changed a friends GTS to Royal Purple Synchromax after he could no longer shift his viper that had 50,000 miles on it with the original ATF in it. Now he has no problems.

Web site: http://www.royalpurple.com/prodsa/scmax.html

 

[Tom F&L GoR]

How do you know it runs cooler?

 

[Bolt]

How do you know it runs cooler?

I do not know that it runs cooler. I'm now running gear lube instead of ATF.

Now that I have put on 150 miles on it I can say there is a 80% improvement with the shifting. I still need to achieve the 100% improvement. More changes to come. Additives? Different gearlube? We'll see.

Bolt

 

[Tom F&L GoR]

Sorry, the question was for Racer Robbie.

 

[Johann]

The fix for this was to go to synthetic gear lube made my Castrol. Castrol manufactures the Mopar synthetic lubricant for these transmissions. This engineer gave me the part number of this lubricant. $18.00 per qt. They do not recommend any other gear lube.

The Mopar lubricant is repackaged 75W-90 Castrol Syntorque, if you shop around you can beat the $18 per quart.

 

[Tom F&L GoR]

It is a 75W-85W.

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http://www.nv4500.com/product_info.php/products_id/24233
$51/gal

 

[Tom F&L GoR]

Or if you don't mind visiting GM dealers, ask for a price on PN #12346190, their rebrand of the Castrol product called GM Manual Transmission Lubricant.

 

[Bolt]

Great post Tom. Thanks!

 

[Bob D]

I purchased the Castrol Syntorq at a local dist. for $179 for 5 gal. ( $8.95 per qt ) and split it with some buddies. Not a bad price that way.

 

[Racer Robbie]

Tom, the trans is running cooler than before as I would burn my fingers in the hot shifter stalk before i put in the Royal Purple. now it is warm to the touch. By the way, I pay $6.52 per QT. I also use it in my off road Jeep wrangler 4 x 4.

 

[Tom F&L GoR]

Phhht on that kind of measurement.

From tap water safety info, here's the water temp and time to third degree burn.

160F - 1 second
130F - 30 seconds
120F - 5 minutes
110F - 10 hours
106F - pain

You won't get 10's of degrees temperature reduction with a transmission oil change coming from Dexron or Syntorq.

 

[Racer Robbie]

Well like I said it feels a lot cooler. It shifts real silky and all the chattering is gone at idle. I am not selling Royal Purple. I have installed it in Customers vipers who have talked with Royal Purple and are convinced as I am that it works. If anyone has any doubts call Randy or Jack at Zero-Altitude-Flight and ask them about their Rt-10 that would not shift. they can be reached at 203-469-4202

 

[Bolt]

Well it's been olmost 2 months now and I can tell you my shifting is 95 percent better. No more hard shifting. This is a must do if you are running ATF and having a hard time getting into gear.

Bolt

 

[Randy]

Well it's been olmost 2 months now and I can tell you my shifting is 95 percent better. No more hard shifting. This is a must do if you are running ATF and having a hard time getting into gear.

I've read the whole thread, and am still not 100% certain which lube you are using and recommending (looks like the last thing you said was that you switched to the stock later-Gen II gear lube?). I've got a 2000 RT/10 - likely already with that gear lube already in it, and I really dislike the transmission feel and performance as compared to the transmission in my 1995 Gen I RT/10. I've been thinking that I might just have a bad tranny (or worn out, or something), and, while I don't really want to risk hurting it, I would indeed like it to be as smooth and solid as my 1995 transmission.

 

[Bolt]

Well it's been olmost 2 months now and I can tell you my shifting is 95 percent better. No more hard shifting. This is a must do if you are running ATF and having a hard time getting into gear.

I've read the whole thread, and am still not 100% certain which lube you are using and recommending (looks like the last thing you said was that you switched to the stock later-Gen II gear lube?). I've got a 2000 RT/10 - likely already with that gear lube already in it, and I really dislike the transmission feel and performance as compared to the transmission in my 1995 Gen I RT/10. I've been thinking that I might just have a bad tranny (or worn out, or something), and, while I don't really want to risk hurting it, I would indeed like it to be as smooth and solid as my 1995 transmission.

Good point, Sorry.

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Bolt

 

[Tom F&L GoR]

Well, they marked it for the New Venture 4500 transmission, but it's a rebrand of Castrol 75W-85W. Yes, there is a difference between "85" and "85W".

 

[418viper]

Personally I'm a believer in what the manufacturer reccomends. Usually the top line suppliers all have good products. What is very important is using the correct viscosity.

 

[ViperJoe]

OK Tom, I bite......what does the W after 85 signify?

 

[Tom F&L GoR]

The use of the "W" indicates there is a low temperature performance requirement and includes a minimum viscosity. (i.e. flows when cold and is at least xx thick.)

Without the "W" there is no low temperature requirement and includes a maximum viscosity (i.e. may thicken and/or solidify at low temperature, and is not more than yy thick."

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In practice, the "W" will require the formulator to use better quality, higher viscosity index base oils. The cheaper high-wax base oils would oxidize more easily, and also fail the low temperature tests. This is a way to **** them out. It's a stretch, but think that it pushes the base oil towards being like a synthetic rather than allowing cheapo stuff.

 

[ViperJoe]

So if it is a rebrand......did they just forget to print the "W" after the 85
or.......is it a lesser quality since it is lacking the "W"?

it's a rebrand of Castrol 75W-85W. Yes, there is a difference between "85" and "85W".

 

[Tom F&L GoR]

Having worked for Texaco, and having a small but significant part of the lubes business being factory fill or private label, and looking at the generous amount of attention paid to the artwork on the label (not), and finally guessing at the total product volume, I would say it was a quickie, slap a label on it and someone forgot the W.

 

[Parisianviper]

Hi Tom,

I switched to a Silkolene 75w90 trans oil, wich is specified as GL5 unlike the syntorq wich is a GL4.
Should I be worried?

 

[Tom F&L GoR]

We have been led to believe by the engine oil categories that the next higher number or letter is the improved product and that they are backwards compatible (newest oil works in older engines.) This is not the convention in gear oils.

GL-4 oils are designed for "yellow" metals which are typically not exceptionally high loads. GL-5 gear oils are for very high extreme pressure performance such as hypoid gears. GL-5 oils will therefore use more aggressive (usually sulfur) additives that may corrode yellow metals like brass synchronizers and some bushings. Differentials that need GL-5 would select metallurgy to work with these additives.

GL-5 applications can't tolerate GL-4 oils; they would wear quickly. GL-4 applications might tolerate GL-5 oils if the metal is compatible with the additives used. And to make it even more interesting, some oils are both GL-4 and GL-5 rated.

It would say that a GL-4 and GL-4/GL-5 oil are fine; an oil that shows GL-5 only "might" be a problem.

Silkolene Silktran SYN 5 75W-90 claims "Suitable for use in most synchromesh gearboxes and final drives — embraces traditional synchromesh gear oil performance (API GL4) and hypoid axle performance (API GL5) in one product." so you should be fine.

 

[Parisianviper]

Waow, that's what I call an answer. You really know that stuff!!
Thanks again Tom.