I was looking at getting some Red Line MT-90 for my X-Runner's tranny but ran across some Royal Purple Synchromax. Anyone have any experience with either or recommend one over the other?
Thanks!
J.
Thanks!
J.
Do not put the mt-90 in your tranny, unless you like the smell of gear oil. I put it in and I would constantly smell gear oil. I think it was coming out of the breather and getting into the cab, because it was not leaking. Get the redline MTL, if your going to change it.I was looking at getting some Red Line MT-90 for my X-Runner's tranny but ran across some Royal Purple Synchromax. Anyone have any experience with either or recommend one over the other?
Thanks!
J.
Demoncleaner, what did you use for the rest? 75W-90 all around?I put 75w-90 Quaker state full syn in at 20K a over a year ago. Its only slightly more than the convential stuff, and not overpriced like the others.
Wanted better flow/protection when well below zero. Not much noticeable diff most times, she has shifted like butter for over 3 years anyway. Changing all fluids to full syn (except LSD) my winter mileage became slightly better.
Synchromax is for transmissions that use a light weight oil. It is essentialy the viscosity of ATF, very thin. You should not use this in a transmission calling for 75W-90 gear oil.I was looking at getting some Red Line MT-90 for my X-Runner's tranny but ran across some Royal Purple Synchromax.
Redline MTL is gear oil, same as MT-90. It is a thinner 70W-80 GL-4 fluid. MT-90 is 75W-90 GL-4. If you were smelling gear oil with MT-90 and not MTL, then it must have been overfilled at one point.Do not put the mt-90 in your tranny, unless you like the smell of gear oil. I put it in and I would constantly smell gear oil. I think it was coming out of the breather and getting into the cab, because it was not leaking. Get the redline MTL, if your going to change it.
Normal 75W-90 gear oil can be used in the tranny (as manual allows GL-5), but with the LSD additives usually included in off-the-shelf gear oils, it is usually too slippery for optimum shifting.
I had the same problem with a new manual trans replaced by the dealer. The problem was, the dealer filled the replacement tranny with bulk 80W-90 gear oil (I asked). As soon as I put MT-90 in, cold shifting was back to normal.Since my transmission blew its reverse gear at 17k miles, I've noticed that the warranty replacement has been VERY stiff when cold. I live in Texas, so cold == above freezing.
Once the trans warms up, it shifts smooth and easy, but until then 1st and 2nd are damn near impossible to select.
I would expect this from a brand new transmission, but I've put about 1400 miles on it since it was replaced, and it still does this.
So what would you suggest instead? 75W-140 maybe? It's thicker, so probably not as "slippery"?Normal 75W-90 gear oil can be used in the tranny (as manual allows GL-5), but with the LSD additives usually included in off-the-shelf gear oils, it is usually too slippery for optimum shifting.
Sorry, what I meant was that most off the shelf gear oils are designed for differentials. They are GL-5 (extreme pressure rated) with limited slip additive usually already included. The limited slip additive makes the oil more slippery so that the diff carrier clutches operate smoothly and don't chatter. What this means is that in your transmission, the synchronizers will have additional slippage, and shifting will be difficult or notchy. 75W-140 is a gear oil meant for differentials under extended high loads, and is too thick for a manual transmission.So what would you suggest instead? 75W-140 maybe? It's thicker, so probably not as "slippery"?
Ring and pinion differentials (front and rear) ALWAYS need GL-5. The pressures exerted on the oil film between gear teeth are so great that special additives are needed to prevent metal to metal contact. A GL-4 fluid here will not protect parts. Front and rear diff should have a GL-5 fluid. Since you have a non LSD diff, you could use either a NS fluid, or a normal diff fluid with the LSD additive included. The LSD additive has the added benefit of increasing the viscosity of the oil at high temps and reduces sliding friction on gear teeth and is safe to use in a non-LSD.Gone, why do you say that? The only difference I can see is that one is GL-4, the other is GL-5. What makes the GL-4 a better choice? Just trying to learn here, thanks for your input.
BTW, which one of the redlines do you think are best for:
1. Front diff (MT-90 or 75W90NS or ???)
2. Rear Diff offroad non-LSD (MT-90 or 75W90NS or ???)
3. Transfer Case (MT-90 or 75W90NS or ???)