6G Celicas Forums

Thanks, glad some people appreciate my madness.

In other news thinking about changing the gearbox oil, can't decide if I want to use 75W-90 GL-4 or Synchromesh though. Did some research and I know the whole cause of our transmission woes. The service manual calls for GL-5, but our transmissions have brass synchronizers. Due to the higher content of sulphur pressure additives of GL-5, it doesn't get along well with yellow metals. The sulphur corrodes and wears away the brass synchronizers, causing the grinding issues our transmissions are notorious for. The million dollar question being, why did Toyota say to use GL-5? Nissan at the time also used brass synchronizers and explicitly called for GL-4. Funny to think possibly how many problems could've been avoided by using the proper oil.

Nissan transmissions are better than Toyota transmissions.

























Said no one ever.

Was about to say, in what world?

I actually have noticed that though, that Nissan recommends GL4 and Toyota says GL5. Personally, I've never had syncro issues in my S54, but I'm running one quart of syncromesh and two quarts of Mobil 1 synthetic 75W-90. Shifts buttery smooth with no issues. The fact that Syncromesh doesn't denote a specific weight on it scares me away from running strictly Syncromesh in my trans.

Synchromesh is 5W-30(according to the good people at Amsoil), only part that concerns me about it. The sulphur does the most damage under high temperature conditions, still it can cause problems as the sulphur does bind with and corrode yellow metals. I'm thinking will just get 75W-90 GL-4, but supposedly lots of people have had good results with the Synchromesh. Best part about the Synchomesh, aside from being cheaper, is that I can buy it locally.

........removed this radiator from a running car.



This post has been edited by ricochet1490: Jul 27, 2013 - 9:23 PM

The whole bottom of the rad is missing.

^How the Hell did it not leak everywhere, or overheat?

My C52 is using Pennzoil Synchromesh. It shifts very well but I never drove a stock ST to compare. The transmission is reported to have a 3rd gear grind, but with this fluid I have not experienced any. Curiously enough, the fluid that I drained out of it was close to water consistency, mixed with mud. Rob, what the hell did you do with this thing?

Noob question - I am running only synchromesh, should I be mixing this with conventional? I was under the impression that it functions solely.

This post has been edited by SwissFerdi: Jul 28, 2013 - 1:06 AM

So many posts to quote but I'd rather not cause then it gets long ugly and confusing.

Just because something says GL-5 doesn't mean it contains sulfur, that's not one of the requirements for it. GL-5 requires that it has to be able to hold up to high speed/shock and low speed/high torque conditions. If you look at a lot of gear oil it actually says GL-4/GL-5 OR GL-5/MT-1.

GL-4/GL-5 are yellow metal safe and don't contain sulfur (this is a good 90% of your conventional gear oil).

GL-5/MT-1 aren't yellow metal safe and most do contain sulfur (this is your specialty gear oil...unless you shop at a truck stop).

Difference is GL-5 is also used in some industrial transmissions which don't use yellow metals for syncros, and MT-1 is used for your big diesels that don't have syncros at all. They use sulfur in them as a friction modifier or some **** like that.

Also just to clear up any confusion sense "Syncromesh" isn't just used by one company - Amsoils Syncromesh is 5w30 GL-1, Pennzoil Syncromesh is 75w90 GL-4/GL-5 and Royal Purple Syncromesh is ATF.

So if you really want your "syncromesh" even though Pennzoil isn't the #1 brand name choice, itd be your safe bet since it won't dissolve your syncros and will actually be beneficial to them. I run a quart of that of in mine since I've had it and its never grinded (except when it was my fault...)



That doesn't surprise me at all that someone would keep using that...

And Box, no it wont leak, those are just the fins missing. They create surface area so that heat is more efficiently dispersed from the coolant passages by the flowing air. Same concept as heat sinks. Overheating wise, its still got a lotta surface area, our a/c condenser actually takes up more space at the bottom of the rad then that. That being said, I wouldn't run that in my car

I need to learn to proof-read...

This post has been edited by travisxcore: Jul 28, 2013 - 12:24 AM

Also duh, no fùcking shìt. I guess next you'll tell me petrol makes cars go and oil keeps engines lubricated? I guess I should've said, "I'm surprised there weren't any holes in the tubes from having so many fins removed."

This post has been edited by Box: Jul 28, 2013 - 1:27 AM

Sulphur is a pressure additive. Therefore in order to meet those requirements it needs? That's right, Sulphur. Sulphur is in GL-4 as well, but in nowhere as concentrated amounts. See the above post for more information.

I'll add that in the rare instance if the EP's are ester based then it can be used in both applications, but out of all the fluids I checked only Motul used ester. Perhaps Royal Purple, but even in their data sheet there was the mention of sulphur.

This post has been edited by Box: Jul 28, 2013 - 3:35 AM

I found some GL-4 80W-90 that runs $6.97 a quart, and for 3 quarts they only charge $4.95 for shipping. http://www.summitracing.com/parts/bpo-023-7729 I'm going to go with with it since it's much closer in viscosity to what our transmission calls for, and it doesn't cost an arm and a leg like Amsoil and Red Line. Synchromesh at the cheapest for me is $7.99 a quart plus tax, and the gas to get to the store and back. Really hard to beat when you think about it. I'd personally be afraid of the Synchromesh being too thin. Take a bottle of it in one hand and a bottle of 75W-90 in other, shake them and you can feel the difference. Or if you want to be more scientific about it you can get a flat piece of metal or plastic and angle it about 10º, then drop a little of each on each side and watch them go.

Here I did you one even better. Here are the product data sheets showing the viscosity of Pennzoil 75W-90 and Synchromesh.

75W-90: http://www.pennzoil.com/wp-content/uploads...-4+GL-5+ALL.pdf
Synchromesh: http://www.pennzoil.com/wp-content/uploads...Trans-Fluid.pdf

Synchromesh is some thin stuff.

mehidcanymorelol.

Today hopefully it'll stop raining so I can go pickup my new tires and mount them on my rims.

This post has been edited by travisxcore: Jul 28, 2013 - 10:23 AM

Oh it was leaking. And overheating in the summer. Reason for that is because under close inspection, you can see what appears to be red rubber all over the rad. My guess, someone poured stop leak down its throat. It's new and shiny now though.

You are correct, thank you for illuminating my ignorance. For safety's sake I should drain a little and stuff some conventional in, last thing I want is a borked tranny.

This post has been edited by SwissFerdi: Jul 28, 2013 - 11:03 AM

Possibly buying a 5th gen Celica for $150 and a case of beer



Also took my car to 160km/h (100mph) the other day for the first time

This post has been edited by rentaspace: Jul 29, 2013 - 1:06 AM

I received and installed Blue Leds from spreeled.com
Also received tein s tech lowering springs, mcgard splinedrive blue lug nuts, rays valve stems and momo handle brake.

I finally had time to play around with my replacement horn button. Checked the fuse, relay, wiring to the actual horns, and tightly attached all wires to the button & horns. It worked! I now have one less item to worry about to pass my safety inspection!