Transmission fluid

[Rat Rod Mac]

Not exactly for a tractor, but did not want to take the time to join the Buick forum because I need to move in the next day or two so here goes. My daughters 2001 Buick Century's tranny blew, so in the process of rebuilding it. Now, do I run the recommended Dextron III or would you go with a synthetic of some sort? If synthetic which one? Thanks in advance. RRM

 

[Texasmark]

My 2011 Silverado uses Dextron VI and has a 100,000 mile power train warranty! Synthetic? Probably. If not why are we all of a sudden getting high mileage warranties and no mention of changing tranny nor diff. fluid in 100,000 miles per the owner's manual?

Mark

 

[Z71]

DEXRON-VI was designed to be backward compatible so it can be used in all Hydramatic transmissions that called for DEXRON-III or earlier DEXRON specifications. If you value the car use synthetic ATF, avoid GM brand.

Just remember with the Silverado: GM only HAS to worry about 100,000 miles...beyond that; (1) it's YOUR problem, (2) they're off the hook, and (3) the stealer-ships MAKE money replacing expensive parts.

Note - Extreme service. For vehicles mainly driven off‐road in four‐wheel drive or used in farming, mining, forestry, Department of Natural
Resources (DNR), or snow plowing change ATF every 45,000 miles.

I use synthetic in everything I value. My preferred brand is AMSOIL

Its been in every vehicle I have owned since 1980 and never had a transmission related problem ever. I put in it my CTS and Denali when they reached 5,000 miles.

 

[3930dave]

I prefer to drive standards, but have gone to Amsoil ATF for my 1 ton, for what it pulls.

Consider adding an upgraded transmission cooler while your at it - at a minimum, check an existing trans cooler for blockages - if the fluid has been neglected, the old trans cooler can be pretty sludged up.

Once it's running again, a low cost OBD II scanner should be able to give you a reading of the Transmission temperature.

Rgds, D.

 

[BuilderML]

Toyota has a sealed system on the trannies.. No servicing.

 

[3930dave]

Toyota has a sealed system on the trannies.. No servicing.

I drive my vehicles too long to trust a "lifetime" fluid. I'm not a fan of most of the manual transmissions being dropped.... somebody was just saying yesterday that there's no stick Camry anymore..... can't say I'd want a lifetime automatic.

Things I don't get about "lifetime" ATF:

What if you have a leak - how do you replace the fluid ?

Once automatics became filled with modern controls, the trani filter became pretty important. Has the filter been done away with on sealed automatics ?

How do you control the transmission peak load, aka temperature ? Modern vehicles have enough smarts to de-power the engine, shut off AC, etc.... to limit how hot the transmission fluid gets - how many light-duty production vehicles do that ? I'm betting few, if any. Folks towing large trailers, with small vehicles, is a common example of a good way to cook ATF fluid.

I don't know CVT characteristics well, yet, so some of these issues may lessen in a CVT application. I'm a pretty simple-minded guy about most things though..... anytime there is a fluid in place, it will break down over time - usually, the higher the operating temperature, the faster the fluid will break down.

Modern synthetic ATF is a better fluid, and if you don't plan on owning a vehicle much past the OE warranty, then that definition of "lifetime" works well.

After having a ScanGauge II in my truck, I'd definitely install one in any automatic equipped vehicle that I bought new, and intended to keep for a long time - knowing the Trans temp alone pays for the gauge, IMO. That data is on the OBD bus already, and modern vehicles have plenty of digital displays - so you should be able to display Trans temp on just about any light automatic vehicle today - I don't know many manufacturers (below 3/4 ton trucks) that allow easy access to Trans temp in their OE dash setup though.

ScanGauge - Trip Computer + Digitial Gauges + ScanTools

Rgds, D.

 

[Z71]

When they say "Lifetime" they mean the life of the part or the fluid. If it fails in 10,000 miles it lasted its lifetime.

It is foolish thinking to blindly believe that everything any auto manufacturer tells you is the "best you can do for your vehicle", is 100% true. There are many, many ulterior motives in any big business when it comes to how any manufacturer of any product represents their products to the consumer.

 

[nahfwt]

That data is on the OBD bus already, and modern vehicles have plenty of digital displays - so you should be able to display Trans temp on just about any light automatic vehicle today - I don't know many manufacturers (below 3/4 ton trucks) that allow easy access to Trans temp in their OE dash setup though.

My 2010 Suburban has the ability to display transmission temperature on the OE display. I would think the Silverados would be able to as well. It has been a really nice feature for towing especially in the summer.

 

[3930dave]

When they say "Lifetime" they mean the life of the part or the fluid. If it fails in 10,000 miles it lasted its lifetime.

It is foolish thinking to blindly believe that everything any auto manufacturer tells you is the "best you can do for your vehicle", is 100% true. There are many, many ulterior motives in any big business when it comes to how any manufacturer of any product represents their products to the consumer.

Part of the motivation for sealed products is driven by consumers..... many people don't want to Hear about, Think about, or Pay for scheduled maintenance. I have my share of irritations with what manufacturers choose to do, but they aren't the only contributing factor here.

I'd be curious to see what Trans temp these sealed transmissions are running.

Rgds, D.

 

[3930dave]

My 2010 Suburban has the ability to display transmission temperature on the OE display. I would think the Silverados would be able to as well. It has been a really nice feature for towing especially in the summer.

It's bad enough up here.... I've been to Dallas in July :fiery: .... it matters even more down your way.

StopNGo traffic in Dallas, dead of Summer, most vehicles probably are running pretty high ATF temperatures - even w/o a maximum load.

I'm coming to believe that many mini-vans work harder in this respect (typical load vs. GVWR), than a lot of pickup trucks.

Since a basic digital display is present on even the smallest car today, the manufacturer can provide Transmission temperature information in an OE dash at essentially no cost.

Rgds, D.