gserep1

Hello,
I was curious about the transmission fluid in the GS's. The manual calls for the Toyota TYPE T-IV fluid. I am not sure if this is a synthetic fluid, or conventional.

I contacted Redline, Mobil 1, and even AMSOIL, and no one has a compatible fluid. I have used synthetic fluids in all of my transmissions, both manual and automatic in other cars. I don't want to ruin my transmission, so I will continue to use the Toyota recommended fluid.

I would assume that most GS owners let the dealership perform transmission services, but I want to start doing my own real soon.

I am also not sure if using the e-shift causes more wear and tear on the fluid and transmission, but I have seen a few units with nearly 30,000 miles on them, and the fluid gets really dark. The factory recommends a fluid change every 30,000 miles during the factory services. That is about as far as I would want to go between changes.

My pre-owned 1999 GS-400 had 36,000 miles on it when I bought it, and the 30,000 mile service was done on time. I will be checking to see how long it will take for the fluid to start getting dirty.

I hope to hear from some of you knowledgeable owners.

Thanks Again,

GSEREP1

Japanimal

Apparently Toyota won't share enough info with the synthetic oil companies for them to certify their atf fluids or to reformulate one that meets Toyota specs. So until they do I would stick with Toyota T-IV. A B&M transcooler should help fluid life and trans durability if tha'ts your concern. Carson Toyota has some pretty decent prices on ATF T-IV. $20 for a gallon if I am not mistaken. Yes, downshifting will cause parts of the trans to wear faster & cause the fluid to brake down faster. Upshifting should not make a difference... unless the shifts take longer when using the e-shift. And by the shifts taking longer I am not refering to how long you hold the car in a certain gear, rather the time it takes your transmission to actually complete a gear change.

gserep1

Thanks again,
You are truly one informed individual, and I appreciate the quick response. I guess that you are correct on this transmission fluid. Toyota will NOT release the specifics on this fluid, and NO one (not even AMSOIL) will certify that their fluid will work correctly in this transmission. Sounds like trans cooler time for sure. I will be changing the fluid earlier than 30K miles if the fluid looks the slightest bit abnormal.

Seems to me that if a transmission were rebuilt with different seals and clutches, then some other kind of fluid could be used, but that is just wishful thinking on my part. Perhaps this fluid IS synthetic...who knows?

If you come up with anything about this fluid in your travels, PLEASE share it with the rest of us.

Thanks again,
Respectfully,
GSEREP1

garnet92

In preparation for installing my new transmission cooler, I stopped at Auto Zone, Pep Boys, and O’Reillys and couldn’t find anything in a type 4 fluid. One of the guys checked his computer to see if there were any alternatives for a ’99 GS4 and actually got a message that indicated that replacements were not available for my make/model.

Apparently the only place you can get the T-IV fluid is at a Toyota or Lexus dealer – and the only thing they carry is gallon sizes. So, to replace a few ounces, I had to buy a gallon of ATF ($19.00).

Being a good neighbor, if any of you local guys want to drop by and borrow a cup of ATF, I’ll be glad to oblige.

Kajukenbo

Hi gserrep1,

Welcome to ClubLexus. I see that you are from San Diego. There are many ClubLexus members here from SD as well. When you get a chance, check you PM.

dmd85059

I've just ordered a case of Amsoil Universal tranny fluid and I'm very dissapointed to find that T-IV is not listed anywhere on the case nor on the bottles themselves. Until they actually print T-IV on the labels, I'll stick with Toyota T-IV.

RMMGS4

iTrader: (5)

Type IV approved synthetic:

https://www.clublexus.com/forums/sho...hreadid=121567