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Sealed CVT

Sealed CVT

I was just reading the the new Scion IQ has a CVT transmission that is sealed. Toyota says the owner will never need to change or add lubricant for the life of the car.

Is this common practice for CVT's?

I suppose if the fluid is exotic enough that Toyota's more concerned about someone adding the wrong fluid than running low on fluid. Still seems unacceptable to me but then I'll never buy a car with a CVT under any circumstances.


The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

RE: Sealed CVT

Ford has been sealing regular automatic transmissions since at least 2002. There's a little standpipe/vent sort of thing on the bottom, but there's no simple way to check/ fill/ drain the fluid.

I think it reflects two things:
- Lip seals have gotten a lot more durable than in days of yore.
- The service infrastructure on the whole does more harm than good.

Mike Halloran
Pembroke Pines, FL, USA

RE: Sealed CVT

I know I started servicing my cars at home after the second time at relatively close timing I had to repair the car on the side of the road on the way home from the dealership. I figured if I had to do it myself anyway, or wait hours for a tow, I might as well do it at home in the relative comfort of my workshop.

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RE: Sealed CVT

My 2001 Lincoln LS had no way of checking the trans and gave no problem in 178,000 miles and eleven years when I gave it to my oldest son. It's still going just fine at near 200k miles. Our current BMW 328IT has no 'dipsticks' whatsoever. No way aside the computer screen to ck ANYTHING. We just had our first 'service' at 16,000 miles. My how things have changed. The dealer, Boris Said BMW of Murieta found that the rear had been out of alignment and the rear tire$ were cupped badly. They replaced two rear tires and did a four wheel alignment along with all the other service at no cost. BMW warranties everything except tires for three years so I was pleasantly surprised that they felt the failure to properly align the wheels was the cause and put on two 255-40-17RF Bridgestone run flat tires at no cost. I know Boris, but I do not think that had anything to do with the service managers decision. I'm happy about it anyway.


RE: Sealed CVT

Hydrostatic transmissions as used in riding mowers of the 90s and probably later claim to be unserviceable.

After 15 years and only a few hundred hours use my dad's Husky mower was reluctant to move forward. Some exterior dampness, but nothing I'd consider a leak. Online resources, some factory related, provided info about what oil to use ( 10W-50 SG maybe ?) and how far down from the vent surface is "full." There is no drain plug, so I just added enough to get back to the right level, and it's working better than it has in years.

Off roaders need to change their fluids after a water crossing.

Lube degrades a few different ways over time, and faster at higher temperatures. Replacement is the cure.
Mechanisms like gears and clutches and probably metallic drive belts generate debris. Lube replacement helps remove that too.

RE: Sealed CVT

While I like to at least have the option to check and change fluids in my cars, I think a magnet and/or filters can remove debris, at least until they clog up.

Maybe oil and filter technology is to the point where the life of the fluids/filters exceeds the expected life of the rest of the car.

Still, as someone already stated, crossing water covered areas can be a problem.

I know that if a hot transmission is cooled suddenly with the breather vent underwater it will suck water in through that vent. I always wonder about that when I see fourbys with air intake snorkels being used extensively in cities.

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RE: Sealed CVT

knowledgeable off roaders are well aware that water can be sucked into a hot differentals and add breather hoses to extend the vents for front and rear differentials up high for the reason you mention..

Some manual transmissions that come in a few off road vehicles already have a small breather tube running up high...

Drive shafts on the vehicles truly designed for off road also typically come with zerk fittings on all joints so fresh grease can be pumped in after running in water..

RE: Sealed CVT


I was actually taking a swipe at pretend rather than real offroaders.

I used to take my old VW beetle past a lot of would be offroaders who stopped because they might scratch some paint off the chassis or get some water on the floor.

I know the guys who regularly drive in the wilderness know what to do.

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RE: Sealed CVT

Opps I hit enter to soon.

Here we call them Tourak Tractors after a trendy fashionable suburb in Melbourne where the furthest off road they actually get is usually the car park at the Polo field.

The rougher ones are attired in fashionable RM Williams cloths with big longhorn logos and have a Blue Heeler in the tray on the back. Unfortunately the poor dog is also only really a fashion accessory.

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RE: Sealed CVT

We call them Mall Runners over here... :<) :<) one guy took his well equipped 4x4 to a mall and ran one of the tires up on the curb for a photo shoot (with glizzy store in the background, of course) and posted it in the 4x4wire off road forum...

RE: Sealed CVT

Key there is "life of the car". All sealed transmissions are done so, mostly to either sell a new car, to ya. or a new or rebuilt transmissio to ya, at the end of the warranty period. This is the main reason for sealed transmissions.

RE: Sealed CVT

"Concrete Cowboys" around here, Pat/Dan... Must have a Banks-equipped Powerstroke or Duramax, absolutely huge exhaust pipe,etc etc. <<<yawn>>>

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