j9fd3s

iTrader: (3)

there are plenty of oem manual shift cars that come with atf in them. the old 323's used atf, bmw lists it as an alternative to gear oil.

GT3_racer

I asked Craig Taylor of Taylor Race Trannies a while back and his conclusion was if you change ATF 2-3 times a season you can run it in a manual tranny, I have in race conditions for years with no significan problems. The debate goes on...

cpa7man

iTrader: (2)

If Taylor says ATF is OK sounds like the MTL should be no problem. I got to meet Craig when hanging around with the Vick Racing guys. He's the man around here when it comes to tranny's.

GT3, Do you run your 85 in GT-3? Or, by chance do you drive the bad *** 3rd gen skined car? Wade McBride I believe, would that be you?

joeracer

In general I agree with you about having a healthy dose of skepticism about a white paper written by a business. Where this one differs is that Redline makes several ATF's, so if they didn't think ATF was a problem, they would have just recommended one of theirs.

Someone else wrote that they use ATF without problem but they change it frequently. That was one of the points of Redline's paper. ATF will work, but the pressures in a manual transmission will destroy the oil within about 5000 miles. If you're changing that often, you're probably not going to have a problem. But on the other hand, what's the point? Why not just use the proper oil?

And yes, once again, the Redline paper states that some car manufacturers recommend ATF in their manual transmissions. That means that those transmissions were engineered to use that type of oil. The question is, are you safe in using it in a transmission that wasn't designed for it. Redline says no. I tend to believe them. My experience is this; Redline says to not use MTL in a differential. Just like the question of MTL vs. ATF in a transmission, they say it can't handle the pressures. I know of someone who blew up 3-4 differentials in their RX7 race car in as many events. He was using MTL. He doesn't use MTL anymore, his differentials stopped blowing up. Hmmm, maybe Redline knows what they're talking about.

If you have to decide what's safe and effective to use in your transmission, you can rely on a group of well educated, experienced and knowledgeable engineers who have run various oils through multitudes of transmission for the equivalent of millions of miles. Those engineers then tore apart those transmission, had the oils chemically analyzed, studied the results of all this testing, made alterations to their products and once again conducted significant amounts of testing.

Or, you can take the advise of some guy on the
Internet, whose only source of information is an opinion and a single car. And the only evidence that this guy is right is that his car hasn't blown up, yet. If that guy on the Internet telling you what to use was me, I wouldn't expect you to believe me. I'm not disrespecting anyone who is posting here. I have my own half-baked opinions about a bunch of stuff in my quest to give me an edge over my racing buddys. I'm just telling you to go see what Redline has to say. There's lots of interesting stuff in the paper Redline wrote, whether you even use their products or not. The choice is yours.

Regardless, this is an interesting conversation and if anyone takes any offense at anything I write, it was unintentional.

-chuck-

peejay

The guy I first got the info from was John de Armond, a hard-core car geek with heavy-duty engineering experience, and he's been using ATF in his manuals for quite some time with no reported problems.

Just to point out how ****-retentive he is, you should Google him on yarchive.net and see how he torques bolts.

j9fd3s

iTrader: (3)

my buddy superbob used atf for years in his turbo chrysler. so i tried it in my 83 and it was fine.

we arent racing though, just driving on the street like maniacs

vipernicus42

iTrader: (4)

If RedLine oils aren't as expensive there as they are here ($20CDN per quart bottle, ouch!) then you should probably get MT-90, which is recommended for our trannies. When it comes to something as tightly engineered as a transmisison, I don't tend to take any chances. Same for me with brakes (but those it's because I have to trust my life to them).

If it's gonna cost you less than thirty bucks to switch, do it. For thirty bucks it's worth not having to wonder if your tranny is gonna dump out on you next time you redline (haha.. gettit?)

RedLine made two different oils (MTL and MT-90) for a reason. There's a purpose for both.. Unfortunatly MTL's purpose isn't our trannies.

Now I'll add my personal disclaimer here: I don't know jack-**** about transmission fluids or the dynamics of the inside of the transmission. This is why I'm going the "better safe than sorry, use what's recommended" route here. It's *possible* MTL will work just fine... but why take the chance that it won't? How much does a tranny replacement cost?

Jon

j9fd3s

iTrader: (3)

yeah, if its that big a deal buy the redline, or some nice gear oil. in my case it wasnt a big deal, as the tranny was a little noisy and 2nd gear was a little slow

peejay

In my case, three or four hours, had the parts already in my basement.

BTW - if you've seen the tranny tailhousing swap page on my website, note the insides of the trannies. That '80 tranny used ATF for a while...

REVHED

Mate, that's nothing. I payed $120 for 3 quarts of MT-90. It was definately worth it though as it completely cured the 2nd gear crunch on my TII. With the previous oil (Motul Synthetic) 2nd gear was almost inaccessible at anything over 6000rpm.

CarlRx7

120$ for 3 quarts?!?!1 WTF. is that in YEN? i payed like 8 bucks a quart from a speed shop down the road.

when i first put the mt90 in i could feel that the tranny was happier. but i still managed to destroy the 3rd gear synchro speed shifting at the drag strip.

carl.

avu3

We switched to MT90 early in the season (85 Pro7), ran 11 weekends (race, test, school) and lunched two trannies - as someone else mentioned earlier, both of them lost synchros in 3rd gear.

Local guys say that the redline is too thin and doesn't provide enough lubrication, and that we should be running one of the Swepco weights. I have not figured out which. I figure to try Swepco in the street car (82 GS) at a track day and see how it goes.

One fellow is an ex rx7 guy who now runs SM and has track records all over, he also builds top level cars - he say not to use Redline in the Maz gear boxes. Another fellow just ran 1.5 hours of a 3 hour enduro with a nearly dry gear box after a crack developed. He finished the event, he was running Swepco also.

Its expensive though, twice the price of MT90.

I don't know anything about running ATF, but I do know many manual trans come with it from the MFR.

Scott