Contour Enthusiasts Group Archives Forums Modifications Transaxle Watch out

I drained the near fresh fluid out last night, looked clean, and put in the RP. As stazi said, it's like butter.

Huge improvement, shifting from 3rd, to neutral, and then to first is a piece of cake, no forcing it into gear at all.

I have three quarts of RP in my trunk, and I can't feel any difference at all in my shifting.

Seriously, though, I am not an experimenter when it comes to most aspects of this car. I let other people do that. So, the good thing is I've missed all the bandwagons: FM, cocktails, MTL, and so on.

From a pure specs comparison, it makes more sense to me to run MT-90 than MTL, but let's face it: Everything I know about MTX fluid I've learned in the last month. Like I said, I'm not one to experiment.

Anyway, I don't have much to go on, here. I posted a response from RP, and I read the responses from Redline, and they both say nearly the same thing. RP inspires a bit more confidence, because they 1) knew what an MTX 75 was, 2) claimed to have "tested" their product in this exact unit, and 3) have enough confidence themselves to cross-reference their product with the XT-M5-QS. The Redline response seems rooted more on what should "theoretically" be OK, unless I read it wrong. Redline doesn't make as bold or specific a claim as RP wrt suitability, either.

Still, there's a lot we don't know about the RP product, and both RP emails are selectively vague about test methodology. What is the test? "No Italians are complaining, so it must be good?"

As TH has said, there could be a quality control issue with the MTL. Based on specs, the MTL should be fine. The MT-90 perhaps "better." Fram oil filters meet specs, too, and thousands of people run them without ever noticing anything wrong. If the quality of the MTL is inconsistent, that could explain a lot. (Doesn't prove it's true, though.)

I'm not interested in "like butter" observations, either. I could put straight ATF in there tomorrow and it would probably shift "like butter" compared to now, (with almost 75k on the original fluid!). My fluid needs changed, and I'm tentatively convinced that the RP is a good product with reliable quality, and that it might even work better than the Ford fluid. But, like I said, I don't have a lot to go on.

The MT-90 is of the correct weight at 75W90. (The same as the Ford "Honey.") As an average consumer, I might not dig any deeper than that. I'm not recommending MT-90. I'm just trying to make a point about "spec."

I run 5w-30 in my engine, and will probably never change. Some guys argue that a 0w-30 or 0w-20 would be better--others argue 20w50. Both cite some arcane technical analysis that I can understand but would never be curious enough to do on my own. Both sides make some believable points that contradict each other. I'll be sticking with the design spec, thank you. That's what I mean by "not experimenting."

Now, reading that you might think I'd never stray from the Honey. But, I think I know enough now to realize that this is not rocket science. Well, it shouldn't be, anyway. My engine wants 5w-30. It gets 5w-30. It doesn't matter who makes it. Sure, some oil works better than others, and I run Mobil 1. But technically, I should be able to run any "certified" 5w-30 oil and not worry about it ruining the engine.

The gearbox is slightly more complicated, I realize. I have to worry about GL-3/4 vs GL-5. I have to use something designed for a synchronized transmission. Given complete ignorance of this thread, I should be able to choose any synthetic manual transmission fluid of the correct weight and GL rating and not worry about it. Given that, I'd be deciding between Redline MT-90, RP Synchromax, and the Ford Honey (and maybe some others). If I didn't know Ford had updated the spec, I might have D4 ATF on the list, but that's a moot point, isn't it? And who the hell's idea was it to put FM in there? But we've already covered that.

If I could wait longer, I would, to get more "long term" data on RP. But 75k is enough, and my shifting needs improvement. I'm going to have to trust my gut on this, and rely on RP's confidence. But I don't see it as a big risk.