T5 World Class Oil

[itempany]

Decided it is time to change the transmission oil. Checked year stamp on transmission and it is 87 so by all means should be World Class T5. Checked oil and it seems to be too thick to be ATF, so seems to be gear oil. Been asking people and looking on line and have been getting conflicting information in regards to either using gear oil or ATF Dexron III auto transmission oil.
I am leaning towards the thinner ATF Dexron III with Nulon G70 as additive as I can't find penrite lubrizol additive any where. What is every one s thoughts on this.

Ian T

[Zedn]

I had a 300zx with one in it. I used ATF with I think 2 tubes of the additive. Can't remember what brand the additive was but it was in a white tube with a picture of the h pattern of a gear box. That stopped 2nd grinding on hard shifts.

[dhs.buckley]

Originally Posted by Zedn

I had a 300zx with one in it. I used ATF with I think 2 tubes of the additive. Can't remember what brand the additive was but it was in a white tube with a picture of the h pattern of a gear box. That stopped 2nd grinding on hard shifts.

I imagine you used Nulon smooth shift, its great stuff, i have used in all my non LSD Diffs and manual boxs, has a teflon treatment in it.
Makes shifting much easier in the 4 speed top loader and the old M21 box in my Wb, also quietens things down if they are getting a bit long in the tooth.

[terry mason]

GM syncromesh work well.

[Aussie Mike]

Just be careful with friction additives. Remember many of them are designed for gearboxes that use brass synchro rings. Most of your modern boxes like the T5 and T56 use organic facings for the synchro rings much like the clutch and brake bands in an auto transmission. This is one of the reasons they specify Dextron fluid.

Here's a pic of a synchro ring from a world class T5



Just check with the manufactures recommendations as to whether the additive is suitable for modern gearboxes.

Cheers

[Texasdoc]

The T5 I had wanted ATF - GM Dexron.