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Royal Purple SynchroMax - two thumbs down...

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fly wheel for a 4 bt help

Saturday night I replaced the Pennzoil Synchromesh in my NV5600 with RP SynchroMax... added a temp guage while I was at it...



First impression: WOW, this stuff is awesome... super smooth shifts, transmission just "glides"... temps ranged up to 175*... but would fluxuate with speed (ie. the faster the hotter)...



I have since put on around 500 miles... and the shifting is worse than with the PZ fill... it is hard shifting... sticky almost... the temp runs right up to 175 at any speed and stays there... and the transmission is nowhere near as smooth as before...



So, I'll be draining it out this weekend for some PZ Synchromesh... at least it held up... really disappointed that A) I am throwing away $50 in fluid, and B) a lot of people on this board have had good results and I wasn't one of them...



So, I doubt I will be using anything but synchromesh from this point on...



steved
 
I had similar results using RP 75w-90 gear lube in my nv4500. I like it in my differentials though. I switched to Redline in my trans and it shifts much smoother with that.



Dan
 
Seems there are a lot of guys running MTL with good results (did a search)... so I ordered a case of it to try...



It is GETTING EXPENSIVE to keep dumping oil down the drain...



steved
 
I've also got one bottle of Lube Gard in my transmission, along with the MTL. Keep it in mind too. Got it at NAPA.
 
Funny how many guys are running MTL in their 6 spd. Redline MTL is a GL-4 75w-90 gear oil, perfect for the NV4500. NV5600s require a 5w-30. PZ and Amsoil are all 5w-30. You guys are running the wrong stuff.
 
Diesel Nut said:
Funny how many guys are running MTL in their 6 spd. Redline MTL is a GL-4 75w-90 gear oil, perfect for the NV4500. NV5600s require a 5w-30. PZ and Amsoil are all 5w-30. You guys are running the wrong stuff.





No, the MTL is a 70-80 weight gear oil, which is very close to 5w30 motor oil... the MT-90 is the GL-4 75-90 gear oil which is closer to a 15W40 weight motor oil... according to their data.



So, they are running the right stuff...



steved
 
Rman said:
I've got 60k on RP synchromax without problems. FWIW



I'm glad for you. . you want 7 more quarts of it for a good price??



I see some people have extremely good luck with it and others don't... I'm one who didn't... I actually ended up almost forcing shifts last night it had gotten so bad so quick... I'm not driving it until it gets changed...



steved
 
Diesel Nut said:
Funny how many guys are running MTL in their 6 spd. Redline MTL is a GL-4 75w-90 gear oil, perfect for the NV4500. NV5600s require a 5w-30. PZ and Amsoil are all 5w-30. You guys are running the wrong stuff.
Like Steve said, a GL 75w-90 IS a 5w-30 on the motor oil scale. And you call yourself an oil dealer? :rolleyes:
 
I am in contact with RP... they want me to send a sample in when I drain it and to get them the batch number off the stuff in there... so we shall see what they have to say about the whole deal...



Like said, it went from totally awesome to totally sucking in around 500 miles... I have no explaination for it. They said they have never had any complaints about before. They asked me the routine questions, "did you fill it correctly?", "is it still full?", "is the clutch system operating correctly", etc.



He told me the temps are in the normal range... I just can't explain the sticky shifting... imagine the notchiness of the NV5600, then make it sticky both pulling out of a gear and pushing into the next... you actually need to apply some force to get out of one gear and into the next.



I'm wondering if there was enough PZ left that it had a reaction to the RP??? But how would you then get all the previous fluid out?



steved
 
steved said:
I'm wondering if there was enough PZ left that it had a reaction to the RP??? But how would you then get all the previous fluid out?



steved
Sounds bad. When I changed mine over I though about removing the PTO cover and wiping out the bottom, but after going through the front and rear meatballs I got lazy and decided to just take out the bottom bolt and let it drain. So I'm sure there was some PZ left in mine.



Bottom line - if it is mixing and reacting with the RP then it is still all bad in my book. Redline MTL didn't have the same issues.
 
nps said:
Sounds bad. When I changed mine over I though about removing the PTO cover and wiping out the bottom, but after going through the front and rear meatballs I got lazy and decided to just take out the bottom bolt and let it drain. So I'm sure there was some PZ left in mine.



Bottom line - if it is mixing and reacting with the RP then it is still all bad in my book. Redline MTL didn't have the same issues.





I had the covers off... wiped (pushed) as much out as I could, but there is still going to be some hung up in bearings and other placed you can't reach...



There are really only two things I can think that might be happening... either the RP reacted negatively with the PZ or the batch of RP I got was off spec.



I have 6 more quarts from a different batch... I'm really temped to try it... just to see what happens...





steved
 
Steved, I did like you and wiped and soaked up as much of the original oil as I could. I drained the RP after 30k just to check it out, and it looked fine, shifted fine and I saw very little sign of wear (my first change was at 15k, I had TONS of chunks from the break in). After draining my first RP oil out I decided to double the change interval to 60k in stead of 30k. I think I'll stick with 60k intervals even if it's ok. That's about 2 years for me, changing it is easy anyways.



I'd be interested to see what RP has to say about it. Mine really does shift nicely. My brother in-law has a 2004. 5 with a NV5600 and mine shifts much better than his. He just has the stock fluid in it. We both have the SB CON FE clutch installed.



Go with what works, it stinks you had to drop 50 bucks though. I don't need RP by the way, I've got 6 qts. left. Once that is gone, I've considered using amsoil's oil. Though I'm beginning to shift away from amsoil, tired of there way of business.
 
It's fascinating how a lube product can produce a wide range of experiences for different people. Some have run Amsoil 5w30 and it was the same thing, some it worked well and for others it didn't. I tried it once and was so-so impressed with it. Someone else who tried it sent in a sample after 30-40k miles and it had sheared down pretty bad, so it didn't appear to be holding up that well. I would say it's because it's a motor oil and not meant for the high pressure, low speed gear meshing and shear/shock loads.



I had the best results with Redline MTL and I don't recall seeing very many have bad results with it. I haven't tried Amsoil's new stuff, mainly because I don't own any 6-speeds anymore, but I think I'd still pick the Redline since it's a little heavier stuff.



Vaughn
 
I have been thinking :eek: Is there a way to flush the transmission out??

Could you put something in the transmission after you drain it, like Marvel Mystery oil?



My plan is/was to:

1. Put MMO in the transmission after I drain.

2. Put the t-case in neutral.

3. Run through all the gears. (no throttle applied)

4. Drain and refill.



Does this pose any problems????
 
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