Alright, now onto the next question: According to this paper, ANY GL-5 oil will cause increased friction wear to brass parts. Basically it states that the additive wear layer package in GL-5 is stronger than the brass, so that as the protective sulphur coating is rubbed away, it actually takes a few microns of brass with it. The way I read the article, it sounds like any GL-5 oil would do this. So just because a GL-5 doesn't corrode brass does not necessarily mean it wouldn't cause this type of friction wear. The factory specs GL-5, so I agree with Brian that they likely just consider the syncros a wear item (kind of like headers). Has anyone here used GL-4 in a 355? Brian, what are your general thoughts on the this given the particulars of the 355 transaxle design?
"Improved" As a marketing guy that makes me laugh. It may have eaten syncros in a week before it was "improved" to have the the syncros last two weeks Hahaha Based on the copper test in the Amsoil report the Redline is fine in that regard. It looks like the Redline does not do very well in the "foaming" area. In the end, overall it appears to be a decent choice. The Amsoil gear oil looks like to be worth a try at some point. Anyone use it?
This is a really interesting thread, in that, as proven again, experience counts more than the marketer's claims. So what about Synchromesh MTF? According to Valvoline's documentation, Mercedes specifies GLS (Special, not 5) in all of their manual transmissions. In addition, before Pennzoil's website/product update, their Synchromesh claims were: Formulated with corrosion inhibitors, a foam suppressor and a shear stable viscosity index improver additive Exhibits excellent low temp performance Excellent synchronizer performance Excellent yellow metal compatibility So reading the labels can be confusing... Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
Very interesting. That sounds like potentially some great stuff, which address a lot of the concerns brought up in this thread. Someone should definitely try it in their 355! Who wants to go first?
Correct. For the few that address it that is the best they say and it is the best said by any non oil manufacturing testing organization. The fact remains that the chemistry required for GL5 is not good for brass. It has become a trade off for the other qualities wanted.
It was my understanding many of the teams used it. I have an old client running around in a 308 with over 125,000 on it that has been using it for a very long time.
You'll have to decide that for yourself. Like Redline, I am not going to tell anyone to run an oil that does not meet Ferrari specification. I will say I have been using it for some time.
Searching finds a surprising amount of people who have second gear synchro issues (mostly from front wheel drive cars) and have converted to Pennzoil Synchromesh. Problem eliminated and "buttery smooth" shifting was/is a common description. However, I haven't read about anyone using it in their Ferrari. Pennzoil has their full-synthetic Platinum® Gear oil for that.
Here is what Mobil has to say about Mobil 1 LS 75W90 (GL-5) synthetic. Mobil 1? Syn Gear Lube LS 75W-90 "Excellent rust, staining and corrosion protection of copper and its alloys"
My concern: That "buttery smooth", especially cold, could be a viscosity that is way too low. Works great cold because it is thin. Once hot does it thin out?? Who knows....but your tranny will wear if it is.
But... it "meets Chrysler specification MS-9224". The Chrysler NSG370 is a six-speed overdrive manual transmission sourced from Mercedes and built in the Stuttgart Transmission Plant. It is Jeep's first six-speed manual transmission and Chrysler's second after the Dodge Viper T-56. The NSG370 does not use standard gear oil for lubrication. This transmission utilizes bronze synchronizer collars resulting in sensitivity to lubricant make-up. Only a fluid characterized by Chrysler specification MS-9224 should be used in order to avoid premature wear or failure of internal parts as well as voiding the factory warranty. Pennzoil Synchromesh is one such petroleum based lubricant. https://en.wikipedia.org/wiki/Chrysler_NSG370_transmission
This is the question to which I responded: Redline has an outstanding reputation with racers who *actually use it* (as opposed to sponsored teams that don't always use the very product they're touting). Their products have been around long enough and are used widely enough that it would have become apparent by now if they were nothing more than marketing hype. Even their competitor's testing indicated that Redline is toward the non-corrosive end of the scale. I am not affiliated with Redline in any way and I have absolutely no idea if NS is the "best" oil to use in any given application, but it seems quite unfair to me to imply that the company's claims about NS's corrosiveness (or lack thereof) is marketing propaganda.
My maintenance records indicate Redline 75/90 NS although I'm not sure what's in the car right now. Right now there's really no shifting problems at all, but I do let the car warm up beforehand. However, I am thinking about Mobil 1 during the next fluid change. I'm interested to hear about yours if you select Amsoil (or any other too).
My experience is just about the same as yours. It's actually allowed me to cut way back on the warmup time-- I now set off slowly after the coolant has come to temp instead of waiting for the engine oil to come to temp (warming the gear oil somewhat during the process). The first couple of shifts to second aren't as smooth as they are when the 'box is warm, but there's no "graunch" like there was before. I still skip second for the first couple of times just for good measure, but I'm OCD about stuff like that. All-in-all, the improvement is marked and I'm quite comfortable having Redline NS in the gearbox. As I've said here many times before, the best shifting 348 I've ever driven had Amsoil in the 'box. So far, NS and Amsoil's transaxle oil are the only oils that I really want to try in my car and I will definitely report back when I do, although it will be a while. I have not been a big user of Amsoil products because their marketing scheme made them difficult to obtain in the pre-interweb days, but from what I've seen firsthand in other peoples' cars they do seem to make some fine products. Their transaxle lube seems to be tailor-made for the 355 gearbox (348s have iron syncros, don't they?) and I look forward to trying it in my car. As with Redline, I have no affiliation whatsoever with either company.
I'm with John on this. M1 is my #1 go to because it is available in my area and it shifts smooth on my cold 2nd gear. Paranoid people can simply ship off an oil sample to blackstone labs for 30 bucks and have an absolute answer of what that a specific oil is doing to their yellow metals. Even if you question the idea of a light oil and its viscosity change at operating temp the lab report will tell you. There is no guessing when you have real data.
We use either the Royal Purple 75w90 max gear or the Mobil 1 same viscosity for all our services. Both work very well and easy to get. Regards, Jim
But the effects of GL5 on brass that we are speaking of is not a matter of rust, staining or corrosion. Sounds like clever obfuscation to me.
I'm really tempted to try the Pennzoil Synchromesh just for my own curiosity. Shoot, it's only about $7 or $8 a quart from Walmart. But I need more info on its high-temp characteristics first. Although my car's trans performs exactly as you describe yours, it was getting a bit stiff during a recent parade (hot day, stop and go traffic for about 20 minutes).
How long or miles using Gl5 like M1 in a box would you feel should show excessive brass in the oil? I'll be glad to put the time or miles in and post the oil report and we can see what happens. I have been using M1 for years and never thought of the potential issues nor have I had any issues but I don't open gearboxes unless I need to either and I haven't.
They do have a good reputation but by the information on their own web site the GL5s are listed as differential oils and the GL4s are listed as transmission oils. In our situation we are dealing with a very narrow portion of the automotive world where we have brass syncros operating in the same oil as a differential, sometimes a hypoid differential and a manufacturer who calls for GL5 while a number of other manufacturers in transmissions with no differential are specific about no GL5. Redline, rightfully so calls for the use of an oil specification called for by Ferrari. In light of the information available about GL5 and my personal experience of repairing a number of transaxles with syncro failures exactly matching those said to be caused by the GL5 chemistry raises the question. Do I favor the syncro life and use a different oil? Unlike the syncros I have seen no unexplained gear wear or failures. I have been using GL4 for years on non hypoid Ferrari transaxles with no issues and have several in service with a lot of miles. In my case at some point it becomes worthwhile to test one of the hypoid transaxles with GL4.
I used Royal Purple in a couple of cars at client request. One came back 2 days later and had me drain it and put Redline back in. His experience with Redline was considerably better. Mine has been too. Never been a fan.
I have no idea how well Mobil 1 either works or protects in a 355 transaxle, but reading that list of attributes reminded me of shopping for racing brake pads-- whenever I look down the list of compounds offered by even just a single manufacturer I can't help but want every single benefit of every single pad. Downsides are seldom mentioned, and if they are it's usually something like "xxx compound provides better disc wear characteristics than our yyy compound". Fortunately, testing pad compounds is a helluva a lot easier and less costly than testing various gear oils. If an oil being GL4 (but not GL5) compliant is critical, it appears as though Amsoil would be a very viable option: https://www.amsoil.com/shop/by-product/transmission-fluid/manual/manual-transmission-and-transaxle-gear-lube-75w-90/?code=MTGQT-EA Brian, many thanks for contributing your experiences to this thread, and indeed in so many areas of this forum. There is no substitute for real-world experience. Is my memory correct in thinking that you have said that the 348 syncros are iron?
You mentioned in the other thread, Agip Rotra LSX (as per the 355 manual as well), which, interestingly enough, is rated for "API GL4+GL5". http://travel.eni.com/catalog/products/documents/001271_1_en_IT_1_106.pdf
This thread is helpful- my car had royal purple put in by the shop that worked on the car before I purchased it ~2K miles ago. My 355 shifts better than my 360 ever did- my 360 didn't shift bad, but definitely took longer to warm up (i.e. shift into 2nd easily vs. the 355), and took a longer time to really loosen up, vs. my 355, and my 355 shifts great- so well in fact that when approaching my road I can easily downshift into 1st gear while rolling- I'm not sure any other car I've owned can downshift into first so smoothly while rolling at 10 MPH or whatever speed I'm going (my daily driver is a 540i w/butter smooth shifter and I don't downshift to 1st). I almost feel guilty doing that though, and therefore typically leave it in 2nd as the car can get up my street without lugging in 2nd, so I rarely downshift to 1st, and don't do it any other time. It is amazing to me that I can do it- a heel toe downshift to 1st if you will Anyway, both my 360 and 355 had similar mileage (I think 25K when I sold the 360, and about 22K on my 355 now). I'm very happy with the shifting of my 355 BUT...after reading the informative posts by Rifledriver and others, I will probably switch to redline or whatever my mechanic recommends. That stuff about the effect of GL-5 on the brass syncros isn't good. The prior mechanic put the royal purple in a few hundred miles before I bought the car, so I didn't bother to change it at the engine out I just had completed...but we were planning on doing it next spring (so I'll have the royal purple in there for maybe 3-3.5K miles). I will contact the prior mechanic to see what type of Royal Purple he uses (the invoice I have doesn't specify type- maybe it's GL-4?) I hope the redline or whatever my mechanic recommends shifts as well as my car does now with the Royal Purple.. Sometimes Wikipedia is useful for quick/succinct info (it seems accurate with what we are discussing in this thread): GL-5 is not necessarily backward-compatible in synchro-mesh transmissions which are designed for a GL-4 oil: GL-5 has a lower coefficient of friction due to the higher concentration of EP additives over GL-4, and thus synchros can not engage as effectively. Also, transmissions which explicitly call for GL-4 oil may have been designed around this lower concentration of EP additives and thus may contain yellow metal parts which GL-5 will corrode. https://en.wikipedia.org/wiki/Gear_oil
