Let's talk about differential and tranny fluids... starting with GM's
05-20-2012, 12:29 PM
#21
Melting Slicks
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I always believed that the Dexron LS was synthetic but thank you for confirming this. Are you saying that Rockland only recommends Pennzoil Synchromesh by brand or just synchromesh fluids in general? (such as RP synchromesh)
At 2000 mile flush (I also believe in flushing out all the break in gunk on new assemblies within a reasonable time) I stuck with Dexron LS for my differential but used Royal Purple Synchromesh for my tranny. The improvement in smoothness was evident on the first drive, and at 4700 miles now, the tranny is simply sweet and keeps getting sweeter. Does not need another shifter or reduced detent modification. To me it is perfect, no grind, no notchiness no noise, positive precise shifts all the time. Like a swiss watch. I do not know how I would improve on it. Or am I just finally (totally bonded with) getting the knack of it?...
At 2000 mile flush (I also believe in flushing out all the break in gunk on new assemblies within a reasonable time) I stuck with Dexron LS for my differential but used Royal Purple Synchromesh for my tranny. The improvement in smoothness was evident on the first drive, and at 4700 miles now, the tranny is simply sweet and keeps getting sweeter. Does not need another shifter or reduced detent modification. To me it is perfect, no grind, no notchiness no noise, positive precise shifts all the time. Like a swiss watch. I do not know how I would improve on it. Or am I just finally (totally bonded with) getting the knack of it?...
To me, it looks like the Royal Purple Synchromax is actually a synthetic ATF product -- probably similar to Mobil 1 ATF, which is the recommended fluid type as per GM.
I just ordered a few bottles of the Amsoil Synchromesh to swap out my break-in oil this week. Guess we'll see if I notice any difference in cold shifting.
Darn you are right...obviously my response posted too early in the morning, eyes and brain haven't synched yet...just not enough synchroffee
05-20-2012, 05:16 PM
#24
Melting Slicks
Thread Starter
. Still have a few weeks to decide, but being a GM approved fluid during warranty is extra piece of mind. Will keep evaluating all different fluids until then. Thanks for all the great contributions gang 
.
05-21-2012, 02:51 PM
#25
Drifting
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Please keep us posted. Looks like I might be the first to try Mobil 1 then . Still have a few weeks to decide, but being a GM approved fluid during warranty is extra piece of mind. Will keep evaluating all different fluids until then. Thanks for all the great contributions gang .
. Still have a few weeks to decide, but being a GM approved fluid during warranty is extra piece of mind. Will keep evaluating all different fluids until then. Thanks for all the great contributions gang .
06-01-2012, 03:04 PM
#26
I installed my rebuilt stage 4 transmission last September and filled it with RP as per the rebuilders suggestion. At the same time I refilled my Diff with the appropriate RP product. I have never been overwhelmed with either's performance since then. The diff was much noisier since and the transmission has felt clunky particularly when cold. As the weather has warmed up the shift feel is improving but that may also be the 8k miles or so I've put on it.
So this thread had reminded I wanted to change. I have considered 2 options, Redline or Amsoil as they seem to get positive comments.
The day before yesterday (5 PM)I contacted subdriver and he gave me a very reasonable quote for both the tranny fluid, diff fluid and slip lock. I paypal'd the money that evening. Mr UPS has literally just dropped off my fluids!
impressive or what? Thank you Brad.
Next week I am going on a 1200 mile camping and road trip with Mrs Alien and I will post up the differences observed between RP and Amsoil.
Excellent thread, lots of use.
Subdriver - top service, many thanks.
So this thread had reminded I wanted to change. I have considered 2 options, Redline or Amsoil as they seem to get positive comments.
The day before yesterday (5 PM)I contacted subdriver and he gave me a very reasonable quote for both the tranny fluid, diff fluid and slip lock. I paypal'd the money that evening. Mr UPS has literally just dropped off my fluids!
impressive or what? Thank you Brad.Next week I am going on a 1200 mile camping and road trip with Mrs Alien and I will post up the differences observed between RP and Amsoil.
Excellent thread, lots of use.
Subdriver - top service, many thanks.
06-01-2012, 04:37 PM
#27
Drifting
Member Since: Jul 2011
Location: Boca Raton Florida
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I installed my rebuilt stage 4 transmission last September and filled it with RP as per the rebuilders suggestion. At the same time I refilled my Diff with the appropriate RP product. I have never been overwhelmed with either's performance since then. The diff was much noisier since and the transmission has felt clunky particularly when cold. As the weather has warmed up the shift feel is improving but that may also be the 8k miles or so I've put on it.
So this thread had reminded I wanted to change. I have considered 2 options, Redline or Amsoil as they seem to get positive comments.
The day before yesterday (5 PM)I contacted subdriver and he gave me a very reasonable quote for both the tranny fluid, diff fluid and slip lock. I paypal'd the money that evening. Mr UPS has literally just dropped off my fluids! impressive or what? Thank you Brad.
Next week I am going on a 1200 mile camping and road trip with Mrs Alien and I will post up the differences observed between RP and Amsoil.
Excellent thread, lots of use.
Subdriver - top service, many thanks.
So this thread had reminded I wanted to change. I have considered 2 options, Redline or Amsoil as they seem to get positive comments.
The day before yesterday (5 PM)I contacted subdriver and he gave me a very reasonable quote for both the tranny fluid, diff fluid and slip lock. I paypal'd the money that evening. Mr UPS has literally just dropped off my fluids!
impressive or what? Thank you Brad.Next week I am going on a 1200 mile camping and road trip with Mrs Alien and I will post up the differences observed between RP and Amsoil.
Excellent thread, lots of use.
Subdriver - top service, many thanks.
Just kidding of course...
Yes would definetely be interested in your report. I have put RP in my stock M6 3000 miles ago, I am very impressed with it as my (stock) tranny is as smooth as you know what. But than I live in Florida so cold temps are not a factor here. I was really tempted to change the differential to RP too, but I will wait to hear from you first. I flushed it but kept the factory fluid in it just to be on the safe side.
But than with the open NPP and lithium blasting on the XM, I do not hear anything else, anyhow...
06-01-2012, 11:28 PM
#28
Team Owner
From my research, it looks to be Castrol Syntorq LT. Looks like it can be bought at both Dodge and GM dealers: http://forums.viperclub.org/threads/...obil-LS-74W-90
Rockland actually recommended the GM Synchromesh, which is in fact made by Pennzoil. So I went with the Pennzoil as it's much cheaper and easy to get. Advanced Auto carries it locally for $8 a quart. I think the GM stuff is twice that price, while being the exact same product.
To me, it looks like the Royal Purple Synchromax is actually a synthetic ATF product -- probably similar to Mobil 1 ATF, which is the recommended fluid type as per GM.
I just ordered a few bottles of the Amsoil Synchromesh to swap out my break-in oil this week. Guess we'll see if I notice any difference in cold shifting.
Rockland actually recommended the GM Synchromesh, which is in fact made by Pennzoil. So I went with the Pennzoil as it's much cheaper and easy to get. Advanced Auto carries it locally for $8 a quart. I think the GM stuff is twice that price, while being the exact same product.
To me, it looks like the Royal Purple Synchromax is actually a synthetic ATF product -- probably similar to Mobil 1 ATF, which is the recommended fluid type as per GM.
I just ordered a few bottles of the Amsoil Synchromesh to swap out my break-in oil this week. Guess we'll see if I notice any difference in cold shifting.
04-18-2017, 09:50 PM
#29
lifetime fill generally means until the warranty runs out, after that your SOL. its surely best to error on the side of safety by changing fluids sooner than later, vettes are not cheap to buy or repairs can be higher cost like any sporty or high end vehicle.
10-29-2018, 06:50 PM
#31
I ordered Amsoil from forum member C66racing for the trans and rear end of my 02 mt6. My car only has 20k miles on it but the fluids were old. Made a huge difference. Both very easy to change, would recommend doing both at the same time. Make sure to include the pump.
10-29-2018, 07:01 PM
#32
i used Amsoil products in the past but found Redline to work better for me!!! since Amsoil answers NO questions about their lubes + only states it is blended to a spec i find dropping above average dollars on their products worth it. you can call Redline + talk to a real person for recommendations as well as use their web site. Ester based lubes like Redline cost more because Esters are $$$, most others use group III highly processed crude oil base lubes legally synthetic + only a bit of PAO + or Ester if any to "meet the spec"
11-01-2018, 07:18 PM
#33
Instructor
ON mine I had the Redline in the transmission and the shift effort is way less than the stock GM fluid also way quieter driveline noise but found that I could consistently beat the synhcros on fast shifts, I could feel the teeth of the gears coging around before engagement so called RPM transmissions and there recommendation was Royal Purple synchro max so I changed it again and the shift effort is a little higher than than the Redline, still less than the stock GM but dont feel the coging of the gears between shifts as much, my conclusion was the Redline was a little too slippery for the synchros so the little extra drag of the Royal Purple is about the best I could get. Also used Redline rear axle oil, did trans and diff at the same time and big drop in noise from the torque tube.
