NAH - How to check CVT transmission fluid?
 

Has anyone checked CVT fluid before? I checked the manual, it says take the car to the dealer to check or to replace CVT fluid, duh!!!

Re: NAH - How to check CVT transmission fluid?
 

nope, but I hear you really don't need to change the fluid

Re: NAH - How to check CVT transmission fluid?
 

The NAH uses the Toyota HSD and a technical group of Prius owners have done lab analysis on ATF wear and tear. From that analysis we determined that the Toyota Type WS ATF does need to be refreshed at 60,000 mile intervals.

The First 60,000 miles show a rapid build up of metallic load in the ATF which was less dramatic in the second 60,000 mile interval. The improvement is due to the gear teeth "lapping in" during the initial period. I will do another analysis on my 2004 Prius at 180,000 miles in a couple of months and have more data.

Given my experience, if I were dealing with a new Toyota-based hybrid, I would do the first refresh at 30,000 miles and then every 60,000 miles thereafter. Of couse some of you could repeat our data collection on your vehicles and determine the appropriate intervals for yourselves.

JeffD

Re: NAH - How to check CVT transmission fluid?
 

Sorry, got lost in the acronyms. Does the Prius have a CVT?

Re: NAH - How to check CVT transmission fluid?
 

The Toyota Hybrid Synergy Drive (HSD) system uses a set of planetary gears to simulate a CVT. It is sometimes called an eCVT or Power Split Device (PSD). All of the Toyota Hybrids and your NAH use this system. Ford uses a very similar system in their hybrids. The Honda Hybrids use a classical form of CVT.

CVT systems have been around for a long time. (see: http://en.wikipedia.org/wiki/Continu...e_transmission) My self propelled snow blower uses a two disk CVT and my 1941 "Servicycle" (I had one as a kid) had a belt pulley CVT, but they are only viable in low Torque/Horsepower systems. Some small cars have been produced over the years with CVTs (Subaru Justy, 1958 DAF, ...)

JeffD

Re: NAH - How to check CVT transmission fluid?
 

I have a 2010 civic hybrid with under 10K miles. It is about 9 months old. I have never check the transmission fluid. How often should this be done or is it done by the dealer at oil servicing. I not adverce the checking fludies if they need to, but If there is no need to I think sometimes things are best left alone. BTW our other car is a 2001 VW Jetta and if you do not check/add oil weekly it will run dry.

Re: NAH - How to check CVT transmission fluid?
 

Your HCH has a modern true CVT that (I believe) uses a belt and cone system. They have been known to have wear problems as they get up towards 100k miles. You should have the transmission fluid drained and replaced (not just checked) at 30k mile intervals if you want to extend the life of your CVT transmission even if the dealer says that it is not required.

JeffD

PS: I also have a 2001 Jetta with only 82k miles and so far it doesn't eat engine oil. Just lucky I guess.

Re: NAH - How to check CVT transmission fluid?
 

Thanks for the advice. What would you recommend as far as checking the dipstick level intervals?

Re: NAH - How to check CVT transmission fluid?
 

It is easy to do the level check if it has an ATF dipstick (My Prius doesn't have one :() so do it when you check the engine oil level. In general, you would get better information about your HCH in an HCH forum (This is a NAH - Nisson Altima Hybrid forum).

JeffD

Re: NAH - How to check CVT transmission fluid?
 

Still quite a bit mystified by the cryptic instructions on checking the eCVT fluid on the Altima Hybrid. A google of the "Nissan Matic W" term led me to the 09-059 service bulletin specifying you must definitely use the W type and not the D, J, or S types most dealerships have for regular CVTs but did not point out the specification or particular equivalents for the W type (a Moss-Magnuson conflict I would think). Then the maintenance and service manuals have a dizzying array of conditions and mileages when one might "Inspect" the fluid versus "Replace" the fluid. The "Inspect" only seems to be a "sufficient level of fluid" inspection and does not indicate checking for color or (god forbid) drawing a sample and sending off to a lab. From TM23 and TM35 I cannot figure how one could get at the side of the transaxle to pull out the little filler plug to just have a look and there is no indication what part number the little gaskets are that must be replaced with every fluid inspection. The inspection seems to be every 15K miles but no clear indication of any replacement ever. If one were to be towing a trailer a lot or "driving on rough/muddy roads" then the 15K interval is a replacement interval. Any comments on how long I could just ignore the whole thing?