I bought my car at 130k miles. It is a 5 speed obviously and I did not really know what maintenance had been done on it. On every new car I get, I like to flush out all fluids to at least know when they were changed.

My transmission wasn't grinding at all. I hear about Redline Synthetic Gear oil, so I decided to put that in. I purchased the 75-90 Weight. When I drained the old oil, it looked semi-dirty. Threw the Redline in, and noticed a difference. The car did shift a little smoother, but then a problem arose. When I tried to throw it in third gear, I heard a horrible grind and was rejected from putting it into gear.

Now keep in mind, I do rev match when I downshift, but many times I grinded third gear. Even when I tried to put it into first going <2mph, it grinded. On cold days, reverse wasn't going to well either.

I decided to do some research on another gear oil. Now, I could throw in the stock Lexus Gear oil, but heard many rave about the smoothness of GM Synchromesh.

Bought it at the local GM dealer. My total with shop discount was 23 dollars. Regular price will run you around 27 for 3 quarts. Drained the Redline and found many metal shavings on the drain plug.

Put in the Synchromesh then took it for a drive. What a tremendous difference. I can now rev match smoothly in all gears. Never grinded 3 gear again. My shifts are extremely smooth and the car has no trouble going into 1st gear at 2-3 mph. In the morning, I can throw it into reverse and not hear a loud clunk. I highly recommend this gear oil.

Let me know if the picture is far too large, and I will resize it.

 

Nice review man. I have read good things about gm synchromesh as well.

 

That's a very good gear fluid and at a bargain, similar to the way that Ford's Heavy Duty brake fluid is also a good bargain with its great boiling points.

 

i used it in my honda once , good stuff

 

this stuff is pretty popular in the honda crowd too as I have used it in my old honda, it really works!

 

I have used it in several personal honda's and customers(200-600whp). Never an issue.(I also used oem honda with out issue also, same with Toyota V160 fluid)

 

Had the Penzoil version which is the same thing but $9 a quart that I got at an Autozone in Michigan when I used to live there. This was in my 500+awhp eclipse in a built Shep Trans and it was smoother than brand new....

 

Shepard Trannies are really good^

Are you on DSMtalk? I'm on there as well, and my buddy has a built 97 GSX.

 

would this work in a torsen LSD?
since this is gear oil

 

Was the Redline 75-90 the correct weight for your gear box? I have always loved Redline proucts in all my vehicles trannies and diffs.

 

do they make this fluid in automatic trans. fluid?

 

IMO, i don't really like the GM Synchromesh fluid b/c sometimes it kinda feels hard to shift and doesn't feels as smooth as the old fluid, but to bad i don't know what's the old fluid is (owner before me must've put it in)...plus it cost me $12/quart and i got 3 quarts from the GM dealer....

 

anyone have any long-term reviews of this product? I've been reading conflcting reports.

Over on the 3si boards they are complaining of silvery, milky trans fluid after putting in the GM Sync.
http://www.3si.org/forum/showthread.php?t=233862&page=8
http://www.3si.org/forum/showthread....254510&page=10

 

Now I am even more confused as to what to use. I was plannning on using the synchromesh in my TH400 but now I am not so sure.

Jonny

 

I cant say how this relates to my SC4 these days as for one I don't use Synchromesh in my tranny at the moment.... But, I came to the SC from 10 years in a Third Gen Z24 (with an Isuzu tranny which is what they came with) that used GM Synchromesh and let me tell you how perfect my manual 5 speed was for all ten years! For that car at least, there is NO WAY I would have switched to anything else but Synchromesh. The stuff was bullet proof.

We'll see over time what the reaction to it is for SCs... but I can only suspect it will be good overall.