What are normal Aisin operating temperatures?

[AH64ID]

I am NO expert but I would think the trans needs some temp to the fluid to function the best.

It does, which is the entire reason that the valve is there in the first place.

 

[Cummins12V98]

It does, which is the entire reason that the valve is there in the first place.

Thanks! I was thinking the same but don't like to say unless I know!

Personally I am THRILLED at how well the system works even towing a combined 33K up long 14% grades locked in 2nd.

 

[Learjet]

My Aisin shifts smoother when at the normal temp range....I would personally not do this.

 

[gsbrockman]

It does, which is the entire reason that the valve is there in the first place.

Don't ya just love how sometimes the aftermarket searches and designs products for a problem---a problem that does not even exist? :-laf

Some how or other, my AS69RC has made it 326,988 miles as is.

 

[AH64ID]

Don't ya just love how sometimes the aftermarket searches and designs products for a problem---a problem that does not even exist? :-laf

Some how or other, my AS69RC has made it 326,988 miles as is.

Yep. I have lots of aftermarket stuff on my truck/engine but it all serves a point/purpose. I don’t like to replace oem stuff just cause, give me a good reason.

 

[DieselLady]

It does not need to be warmed up to work properly. Also when this part fails, it fails in the closed position, you will smoke the trans if you don't stop. My truck is an 08 and they never put any check valves on it. Normal operating temp is 168. I like having some room to spare in case it needs it. ")

 

[Newsa]

I realize a standard transmission is completely different than an automatic.

The automatic relies on the ATF much more than the manual transmission.

The automatic relies on the fluid to transfer power & lubricate. The manual relies on the ATF for lubrication. Both rely on the fluid for cooling.

If you have ever tried to shift a G56 when the fluid is at nearly -20°F, you know that the auto is also dealing with a whole different animal in the cold. Even if the transmission is programmed to operate in cold weather (because it has a temp sensor), it still will not work as well in cold temps as it will at operating temps.

Why wouldn't you want your transmission to warm up quicker? It will work better and provide better fuel mileage

 

[kthaxton]

It does not need to be warmed up to work properly.

But it is most efficient and you get the most longevity, when it is at its designed operating temperature range....which is usually in the 180º (or slightly less) range. This is the same for any lube filled mechanical doohickey.

 

[AH64ID]

It does not need to be warmed up to work properly. Also when this part fails, it fails in the closed position, you will smoke the trans if you don't stop. My truck is an 08 and they never put any check valves on it. Normal operating temp is 168. I like having some room to spare in case it needs it. ")

No different than the engine thermostat, but we watch our gauges and should pull over if something is awry.

It's likely not a check valve either, it's going to be a thermostat or a thermostatic bypass valve... I can't tell which from your photos.

The valve does nothing to give you more temperature room to spare, it simply allows the transmission to warm up quicker and maintain temperature in cold/low load environments.

You really think they put it there for funzies? If it wasn't in your 08 and it's now on the new trucks I'd be considering adding it to the 08 vs removal from the new trucks. Updates like that generally happen to either improve mileage or increase longevity, or both. Neither of which is bad.

 

[DieselLady]

I don't know where you are but here in Southern Calif we don't need to warm them up quicker. Ya maybe if you live in Alaska, or canada but not here. The problem is, your talking about extremes. In most of the states you really won't have any difference if you warm it up. But you will have a prob if it sticks shut like we see it doing. Auto trannies do not necessarily need to be at 150 or more degrees to perform any better. ATF+4 does not get thick at normal cold temps. I can't speak for minus 20 degrees. But most trannies will not allow lockup till it's up to a certain temp in extreme cold temps. But for all the rest of us. it takes about 5 mins of driving to see 100 degree temps, so why would you want it to be made hotter faster? Heat kills. Also, I do not want to have to worry about being broken down on the side of the road when this thing decides to stick shut. Just sayin.

 

[gsbrockman]

Having followed LOTS of different forums over the years and having been in the 2007.5 & up forums since 2007, I have only heard of a handful of failures of the TBV (thermal bypass valve). Guess what---those noticing an issue were able to notice the problem because they actually monitor their displays /gauges and caught it without any ill effects. In addition, those with bad TBVs usually had to wait on the new TBV a few days as---guess-what---dealers did not stock them as the failure rate was so low. My 2007.5 RAM 3500 w/68RFE had the TBV. The temperature drops claimed in post #18 seem a tad sketchy to me.

On my last run to Marietta, GA I witnessed 83 RAM/Cummins automatic trucks broke down due to faulty TBVs.

#ad

 

[kthaxton]

I don't know where you are but here in Southern Calif we don't need to warm them up quicker. Ya maybe if you live in Alaska, or canada but not here.

There's a whole lot of country besides SoCal and Canada and Alaska...plenty with cold temperatures.

The problem is, your talking about extremes.

Actually, you are talking extremes (SoCal to Canada/Alaska)

Auto trannies do not necessarily need to be at 150 or more degrees to perform any better.

Do you have data to demonstrate this? I can produce data to the contrary.

ATF+4 does not get thick at normal cold temps.

It's not only about the oil, it's about the various metal components (different metals with different expansion rates mind you) of a transmission that are made with tight tolerances and are designed to work optimally, at a certain temperature range.

I can't speak for minus 20 degrees. But most trannies will not allow lockup till it's up to a certain temp in extreme cold temps.

Yeah, there's a reason they want it to warm up to a certain point.

But for all the rest of us. it takes about 5 mins of driving to see 100 degree temps,

You're painting with a wide brush, I am not in Canada or Alaska and I can feel my trans be a bit sluggish in the single digits or even in the teens. Further.....it certainly takes me (and the rest of us ) more than 5 mins to see 100 degrees when it is cold...and that doesn't mean only at -20.

so why would you want it to be made hotter faster?

lol...you need to explain why you WOULDN'T want it at temp (note: "at temp" instead of "hotter") faster! It is a cold hard fact, the longer a transmission is cold, the less efficient it is....and the more wear it sees over time. Same goes for the fluid if any condensation doesn't get ample opportunity to evaporate.

Heat kills.

Yep, tis true...'cept your fix isn't fixing a "heat" problem. It is a solution looking for a problem.

Also, I do not want to have to worry about being broken down on the side of the road when this thing decides to stick shut. Just sayin.

...and this is your ONLY legitimate "fix"....and as Brockman said above, it's not even a very good one.

 

[Learjet]

Doesn't the proper temp also helps the moisture evaporate ??

 

[AH64ID]

I cannot look at 08-09 68RFE data but the 10+ 68RFE won't lock below 55°F, hardly extreme.

For reference the 48RE won't lock below 70°F, even less extreme.

 

[gsbrockman]

I cannot look at 08-09 68RFE data but the 10+ 68RFE won't lock below 55°F, hardly extreme.

For reference the 48RE won't lock below 70°F, even less extreme.

As far as the 2010 68RFE is concerned....is 56*F the temperature at which additional shifts are allowed ? I do not know the exact temperatures, but some gear shifts are not allowed as well.

 

[AH64ID]

As far as the 2010 68RFE is concerned....is 56*F the temperature at which additional shifts are allowed ? I do not know the exact temperatures, but some gear shifts are not allowed as well.

I can't see anything in the tables I can view that prohibits shifts. I do see tables that delay shifts based on cold trans temps but not by a huge amount.

 

[DieselLady]

Having followed LOTS of different forums over the years and having been in the 2007.5 & up forums since 2007, I have only heard of a handful of failures of the TBV (thermal bypass valve). Guess what---those noticing an issue were able to notice the problem because they actually monitor their displays /gauges and caught it without any ill effects. In addition, those with bad TBVs usually had to wait on the new TBV a few days as---guess-what---dealers did not stock them as the failure rate was so low. My 2007.5 RAM 3500 w/68RFE had the TBV. The temperature drops claimed in post #18 seem a tad sketchy to me.

On my last run to Marietta, GA I witnessed 83 RAM/Cummins automatic trucks broke down due to faulty TBVs.

#ad

Excuse me but the thermal check valve was not introduce until 2013. And yes we have seen tremendous drops in trans temps! In my shop we have seen 3 failures this year and my dealership has them in stock! I am not one to exaggerate in order to get attention in the forums. Just putting out info from my own experience! Your welcome to take a chance with your truck! I have a lot of money in my trans and don’t exactly feel like chancing getting stuck in the middle of the Mojave desert! But I am not exaggerating the temp drops! You believe what you want!

 

[Cummins12V98]

They can replace mine if it fails for 100K. OH and fix any damages.