[Ventmaster]

Link to the previous text from cadyshac- https://www.camaro6.com/forums/showthread.php?t=629403

I have used RP 75/90w and got temporary relief from the cold crunch but it did not last. I haven't tried the Synchromax because it didn't seem to be the appropriate choice. My '86 Camaro used ATF in the manual trans, but I believed this trans required gear oil. No issues with the Synchromax?

RP says Synchromax viscosity is "low". But also sez it's appropriate for manual transmissions (now-I don't think it always had that on the label). Did they used to offer something Synchromesh as well or am I just making that up- lol.
Any other opinions?

[Ventmaster]

OK- think I answered my own question about oil names: RP sells "Max Gear Oil" and "Max ATF". I'm still concerned about the low viscosity. OE gear oil in these cars has a top viscosity rating of 80w when warm if I remember correctly. I'm sure the AC Delco gear oil called for in the diff is 75w90 with LSD additive (that's "limited slip friction modifier" for the other old hippies out there-lol).
So, no one's blown up their trans with this Synchromax MTF? All the retailers I'm looking at say that it is for manual transmission cars if the manufacturer specifies it can use "automotive" transmission fluid. Hmmm... Does that mean ATF like my old 3rd gen car?
Last update- MY OE gear oil for the manual trans is a 75w-90. RP Synchromax has a viscosity of 10. Despite the front label saying it is a "High Performance Manual Transmission Fluid", but the fine print sez it is "recommended for manual transmissions that specify an automatic transmission fluid or motor oil".
Some retailers use "automotive" instead of automatic trans fluid and describe the viscosity as "low (relative to motor oils)" in order to mislead I believe.

[bishopts]

This is an odd rabbit hole of a thread. Most places say GM manual trans fluid for the camaro which is supposedly 75w90, but mustangs running the same tr6060 use ATF. Very odd.
I remember my trans am had a t56 with ATF also.
I might just drain my trans and fill it with engine oil.

[Ventmaster]

Originally Posted by bishopts

This is an odd rabbit hole of a thread. Most places say GM manual trans fluid for the camaro which is supposedly 75w90, but mustangs running the same tr6060 use ATF. Very odd.
I remember my trans am had a t56 with ATF also.
I might just drain my trans and fill it with engine oil.

Yes, it is odd. There are two main types of gear oil available in the market: API rated GL-4 and GL-5. GL-4 and GL-5 gear oils differ significantly in their extreme pressure additive content. GL-4 gear oil contains up to 4.0% anti-scuffing additive for protection against wear for moderate-speed and load applications. GL-5 contains up to 6.5% anti-scuffing additive and is designed for high-stress, high-speed, and high-load conditions.
These additives (sulfur compounds- that's why gear oil smells so bad), can be hard on brass components in the trans. Our cars call for a GL-5 rating for oil in the manual trans. RP does not provide a GL rating for Synchromax. I have read that due to kinematic viscosities(?) that a synthetic motor oil of 10w-40 would be roughly equivalent to 90w gear oil, but that would be without the high pressure protection additives.
Which leaves the question open- is Synchromax (which is obviously an ATF being marketed as manual fluid) safe for use in the Camaro 6th Gen manual trans?
According to Bob the Oil Guy, "Most of the "MTL" or "Synchromesh" fluids carry a a GL-4 or lower rating." Combined with a viscosity rating of 10, that makes me nervous about using it in my car.

[N Camarolina]

Originally Posted by bishopts

This is an odd rabbit hole of a thread. Most places say GM manual trans fluid for the camaro which is supposedly 75w90, but mustangs running the same tr6060 use ATF. Very odd.
I remember my trans am had a t56 with ATF also.
I might just drain my trans and fill it with engine oil.

Might be because the Mustang doesn't use the TR6060, but rather the TR3160. Maybe the internals are different.

Or if internals are near identical, it might be what GM vs Ford thinks is the most appropriate lubricant since they are the ones to provide the warranty. Notice that when Tremec more recently came out with their own fluid for the TR6060, it's significantly more viscous than the GM specified trans fluid (probably better for heat protection at the track, but also more "crunchy" when cold).

[bishopts]

Originally Posted by N Camarolina

Might be because the Mustang doesn't use the TR6060, but rather the TR3160. Maybe the internals are different.

Or if internals are near identical, it might be what GM vs Ford thinks is the most appropriate lubricant since they are the ones to provide the warranty. Notice that when Tremec more recently came out with their own fluid for the TR6060, it's significantly more viscous than the GM specified trans fluid (probably better for heat protection at the track, but also more "crunchy" when cold).

Gt500 cars used the tr6060, i forgot but the dodge challengers did too and they also used ATF.
The rabbit hole goes further lol.

When i was in tech school years ago, the instructor for drivetrains was going over locking hubs for front axle trucks. He was saying it was pretty standard for people to build those and use axle grease for the lubricant. But he used engine oil instead, he was telling us how the engine oil being thinner would be much less suseptible to resistance to move in colder weather. Unfortunately i never had a chance to build a locking hub that didnt happen to be lubricated from the axle itself.

That being said I'm pretty sure the OP car just has a messed up 2nd gear synchro. No lift shifts and bad timing with the clutch pedal a couple times and you round off the teeth on the blocker ring and synchro cone teeth.
I got my car used and i can feel 4th is a little "notchy" compared to the other gears. Luckily i don't really use it very often because i usually shift 1st 3rd 6th, but eventually i will need to pull the trans to do something and i will pop it apart and replace whats needed.

[cadyshac]

I too bought my car used and I can't help but feel like previous owner tried cramming it into 2nd when cags was initiated. I have skip shift installed so got rid of that problem. Currently I am running the Tremec fluid but weather was cold when I put it in and I've only driven the car a few times since the fluid switch from Royal Purple to Tremec. Snowmageddon hit a week ago so car is just sitting for now but the Tremec fluid did not solve my problem.

[N Camarolina]

I think this thread is starting to spread incorrect info, at least based on several previous M6 threads. I'll try to correct here for the benefit of others that might be newer to the forum:

1) The OEM fluid for the TR6060 in a G6 Camaro is some kind of ATF, which is not the same as the 75-90 gear oil in the rear diff. I do my own maintenance and the M6 fluid is red and I believe it is thinner than the rear diff gear oil.

2) TR6060 seems to have some extra resistance and/or "gear nibble" going into 2nd gear when cold (the beginnings of gear grind if you apply light pressure as you attempt to move the shifter into 2nd), especially in low ambient temps). I've personally even seen this for 3rd gear as well (the gear nibble part) sometimes. But after 1/2 mile or so of driving, this all goes away as the fluid warms up.

3) Owners have experimented with non-OEM fluids to try to improve the problem. RP (can't remember which specific product) was reported to help quite a bit, but eventually loses it's magic touch and needs to be replaced. The prevailing thought on why RP seems to work is that the problem is related to viscosity. RP is supposedly thinner and helps lubrication when the trans fluid is cold. Tremec fluid is at the opposite end of the viscosity spectrum (thicker than OEM and definitely thicker than RP), and from the few owners who've tried it and reported back, the problem is worse than OEM when cold. Tremec fluid may have been developed for better protection/shifting action under track conditions, when fluid is hotter than normal road driving.

There are some additional possible risks with RP that you should consider if you intend to use it: 1) Being thinner, it likely will not protect as well as OEM/compatible ATF or Tremec fluid at higher temps (canyon runs, tracking) 2) If I recall correctly, it doesn't meet the trans fluid formulation rating called for by GM/Tremec. Some of the Tremec innards may not be chemically compatible with and may be degraded by fluids that don't meet the OEM trans fluid spec. No idea what's in the RP, but use it at your own risk.

[Ventmaster]

+1 on each of your points N Camarolina with extra attention to use ATF at your own risk. And yes Synchromax may be representing itself as MTF, but only for cars with a manual trans that specifies to use ATF.
Too many folks are referring to RP without adding which one they are referring to.
IMHO we need the gear oil in the 75w-90 range and have to live with the colder weather requiring a little patience, a skip shift blocker so you can do 1st-3rd gear shifts when cold, and possibly a synchro replaced if it has seen too much abuse.
BTW N Camarolina, what part# does your manual call for the manual trans?
Mine was GM part# 88861800 (or AC Delco # 10-40330). I didn't recall it being red, but I could be wrong.

Of course I ran across this cross-reference chart made by Royal Purple. Their phone # is 888-382-6300 for technical questions.
https://www.royalpurple.com/wp-conte..._Reference.pdf
At the top it sez use the Max Gear oil if your trans calls for 80w-90 oil and at the bottom says if 88861800 is called for use Synchromax.
Who knows!!

[Warrior102]

The TR-6060 specifies ATF, not gear oil. Mobil1 ATF, Redline D4, AMSOIL ATF or a MTF (RP Syncromax) among others can be used. I currently have 45K on my 1LE with RP.

https://en.wikipedia.org/wiki/Tremec...0_transmission

[SWFLZL1]

My ZL1 M6 had atf in it from the factory, and calls for atf as a replacement. I ran the Tremic fluid when I changed mine out, and it seems to shift about the same as the factory fluid, before it’s warmed up. I do live in Florida though, so we don’t see real cold.