Tranny temperatures 1HDT A442F

[jcolvin]

Who has a tranny temp gauge?
Where is it (in the output line or in the pan)?
What readings do you get?
Do you have additional cooling?

My observations:

My temp gauge sender is in the output union (not the pan).

My temperature will spike up to 140+ C (high!) if I'm powering up long hills out of lock-up in 3rd (ie. not quite enough power/too steep a hill to get up the hill in locked 4th). Now this is the temperature coming straight out of the torque converter, NOT the overall tranny oil temp (ie measured in the pan), which should be quite a lot less.

I've found that I can stop this happening by shifting down (ie. to 2nd) and keeping the revs high (ie. above 2600 RPM). Then the temp only goes up to 110 C or so.

So when powering up big hills heavily laden or out of lock-up, keep the revs up above 2600 RPM to avoid burning up your tranny. This is probably nicer on your EGTs too.

 

[Martin White]

Jonathon, I just had an ISS Pro gauge installed for AT temp and the probe is in the pan oil. I haven't done any LONG hills yet, but the absolute highest temp I've seen (1 hour of freeway running) is about 162 degrees F. Dunno if it's gonna' go higher or not. I will try it on Cypress when I get a chance and add to this thread, if I remember. I hope that helps a bit. Currently, no additional cooling. But if I see temps I don't like, I won't hesitate to add cooling.

 

[wussyPup]

I'm still over 2 weeks away from re-install. I will post numbers afterwards.

I will install a remote cooler and am planning to have a thermostat so that it allows the temp to rise to operating level.

Here's a pic of the gauge kit

I don't have install instructions yet so don't know where it will be plumbed in - I assumed that it would be at the transmission on the way to the oil cooler.

When I cooked my tranny, engine was at about 2200 RPM and transmission held in 3'rd gear; it would have held OD if I let it, but I was concerned about EGT (no gauge) so had shifted to 3'rd.

Jonathan's numbers are very interesting (and helpful), and not what would have expected.

Thanks! -Steve

 

[70sguy]

It sounds like Rodney's Extreme Valve body is a a worthwhile investment as heat is the death of these trannies.
Getting lockup in 3rd seems key to keeping the tranny temps down during climbs where there either isn't enough power or too high EGTs to stay locked in 4th. Adding a tranny cooler seems like a no brainer as the HDJ81s only have the heat exchanger in the lower tank of the rad. Where the US FZJ80 has the rad tank tranny cooler as well as an air cooler. I stayed with both coolers when I swapped to 1HD-Tw/ECT type A442F with EVB into my US FZJ80, Unfortunately I do not have a tranny temp gauge on there yet so I have nothing scientific to offer. I Love the Extreme Valve body though!!


http://www.automatictransmission.com.au/news.asp

 

[wussyPup]

hopefully this is just a minor hijack...

Sheldon, which ATF are you using in the A442F, and are there others that you recommend?

-Steve

 

[expat]

I'm still over 2 weeks away from re-install. I will post numbers afterwards.


Thanks! -Steve

That's one of Rodney's kits isn't it? Where did you purchase?

Mike

 

[wussyPup]

That's one of Rodney's kits isn't it? Where did you purchase?

Yes. I bought an Extreme changeover A442F and his recommended gauge from Rodney. It's at sea now; the ship should reach port in about a week.

 

[70sguy]

I am using Amsoil. I am sure there are other good synthetics.. Rodney mentions some on his site.
If you are getting an extreme A442F on exchange you better hope they don't send back the later 9208 up A442F with the multi solenoid valve body that requires ECT computer control and a TPS on the injection pump. They look the same from the outside.
The fact that they call the tranny in the JDM 9001-9208 HDJ81 an A442F has me somewhat baffled since the tranny really is more like the A440F that comes in the 9001-9208 FJ80.
Rodney is probably up to speed on the oddball JDM HDJ81 A442F tranny and valve body by now.. As far as I know it was sorted out when Marko of Outback got his HDJ81 valve body switched over to an extreme unit, after much weeping and gnashing of teath mind you....
Might be worth a check.. you'd hate to get the wrong tranny shipped half way across the planet.

 

[wussyPup]

I am using Amsoil. I am sure there are other good synthetics.. Rodney mentions some on his site.

Thanks Sheldon.

Might be worth a check.. you'd hate to get the wrong tranny shipped half way across the planet.

Oh great! Now, I'll really sleep well tonight.

Actually, Greg warned me about this in advance, and I did discuss it with Rodney. But, I guess there's always the possibility of an oops. I'm hoping this won't be my turn for one.

 

[jcolvin]

I will install a remote cooler and am planning to have a thermostat so that it allows the temp to rise to operating level.
I don't have install instructions yet so don't know where it will be plumbed in - I assumed that it would be at the transmission on the way to the oil cooler.

When I cooked my tranny, engine was at about 2200 RPM and transmission held in 3'rd gear; it would have held OD if I let it, but I was concerned about EGT (no gauge) so had shifted to 3'rd.

Jonathan's numbers are very interesting (and helpful), and not what would have expected.

Thanks! -Steve

That's the same temp gauge as I have...one of Rodney's. It measures temp straight out of the T/C on the way to the cooler, so you will see temperatures much higher than those who are measuring in the oil pan.

I'd love for an experiment to have another temp gauge in the oil pan to see how long it takes for the overall tranny temp to rise.

I have a feeling that a problem with this A442 tranny is that the torque converter can get REAL hot (hot enough to start cooking stuff) before the rest of the tranny has a chance to heat up. In this case a temp gauge in the oil pan may not let you know in time; and all the external cooling in the world won't help.

I think this is why Rodney plumbs his gauge into the outlet rather than into the pan.

Yep, 2200 RPM is in the danger zone I've noticed (at this RPM in 2nd I once hit 150 C and my tranny temp warning light came on because I wasn't paying attention to my tranny temp gauge). Seems that this RPM lets the engine generate lots of tranny-cooking torque, but the converter is not fully stalled (I'm guessing). Revs of 2600 RPM and above seems to help matters.