Engine/Transmission (1998.5 - 2002) Need some help, Issues with a NV5600

[c-hawk]

I recently changed the fluid in my 5600 to redline mtl. Shortly after that, the weather around here started getting cooler and i noticed that when the truck sits for a while, it is real tough to get into 3rd. Once the truck has been driven for a little bit, 3rd is smooth as can be.



I'm probably going to try going back to the factory fluid and see if that fixes things, but i'd like to know if anyone has any input on this.



What would cause 3rd to be hard shifting and grind a little when cold, but shift perfect once warmed up a little? Does a syncro do that when going bad?



Thanks,



Chris

 

[Gary - K7GLD]

I recently changed the fluid in my 5600 to redline mtl. Shortly after that, the weather around here started getting cooler and i noticed that when the truck sits for a while, it is real tough to get into 3rd. Once the truck has been driven for a little bit, 3rd is smooth as can be.



I'm probably going to try going back to the factory fluid and see if that fixes things, but i'd like to know if anyone has any input on this.



What would cause 3rd to be hard shifting and grind a little when cold, but shift perfect once warmed up a little? Does a syncro do that when going bad?



Thanks,



Chris

Been there, done that!



Sometimes, in our unending quest for the "very best" for our trucks, we shoot ourselves in the foot - AND wallet!



I tried to improve on the factory lube too - not because of any issues with the stock stuff - just wanted "better"...



I first tried Amsoil - it made a decent shifting transmission worse - went back ro the stock stuff - all was well again - until I next figured I was smarter than the folks who made the transmission, and decided to try Redline MTL...



Again poor shifting - grinding between 2nd and 3rd, and from 4th to 5th. SOOooo, now about $80 poorer, I again refilled with the stock stuff, again all is well - and just MAYBE this time I have learned my lesson... :-laf

 

[kscheffler]

I have always used the factory oil, since I bought 3 cases when new for 9. 00 per quart. My 5600 has always been notchy going into 3rd. I talked to new venture about the problem after I first purchased since the dealer was saying it is "normal" for this transmission. Anyway, NV suggested double clutching on 3rd and I have been since the first two K and never have any problems. Once I get the tranmisssion oil above about 115 to 120 it will shift without double clutching. I can live with this no problem...

 

[Sea01Cummer]

How much is the mopar fluid??



Steve

 

[mhuggler]

I chose mtl-90 instead of the regular mtl and got a huge improvement in shifting. It's been in there for at least 20-25k miles and still works great!

 

[Gary - K7GLD]

Casual readers here should be aware, the NV5600 is *NOTORIOUS* for substantial differences in sensitivity to various lubes!



VERY often, what works well in ONE transmission works lousy in another - there definitely is NO "one size fits all" where these trannies are concerned - so if you choose to experiment, or base YOUR choice of alternative lube on what worked well for good 'ol Guss - be prepared to see entirely different results in your own 5600 - it happens all the time!



It's also worth pointing out (again!), that these 6-speeds are NOT like the 6-speeds in a Corvette or similar sporty type car - these are TRUCK transmissions, made for hard WORK, not dragstrips. Treat them with decent care and respect, and they can last a lifetime - abuse them, and well... :-laf