What external transmission cooler for an FJ62?

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I love LCNW! Coincidentally, I was in there two weeks ago to get their opinion on my transmission that was acting up. Part of me was hoping the auto trans was toast and I would need to drop in an H55F, but it turns out that I just needed to replace the kickdown cable.

What symptoms are you having?
 
lechnito said:
I love LCNW! Coincidentally, I was in there two weeks ago to get their opinion on my transmission that was acting up. Part of me was hoping the auto trans was toast and I would need to drop in an H55F, but it turns out that I just needed to replace the kickdown cable.

What symptoms are you having?
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I was having trouble holding speed. With the RPM's constant the speed was dropping.
 
After my trans temp light started acting up, I installed a trans cooler. But while I was intalling it, I noticed that the rubber cooler lines that connected between the solid cooler lines had a slight twist in them, and the rubber had formed a memory of it. (Rear of the engine oil pan area). When I tried to straighten them out, the solid lines broke due to rust. I replaced the entire run with high temp rubber hose. So far all is good! It was just a slight twist/crimp in those rubber lines. I also moved the temp sensor connector away from the solid trans fluid lines at the transmission. It was hanging close enough that I thought it might be giving extra heat to the sensor. I have not confirmed that was the case though.
 
Can someone here do me a huge favor and confirm which hose is the return line back to the tranny? On the radiator, does it connect to the passenger side fitting or the driver side fitting?

After once more getting the AT temp light while climbing up a steep 2000 foot grade, I've finally given up and started the process of installing the Hayden 679 that I ordered a few months ago. I just finished fabricating up some brackets out of a 1/16" thick aluminum bar and have the new cooler securely mounted in front of the radiator. I suspect it's the passenger side fitting has the return line but I wanted to double check since this detail is not mentioned in the FSM.
 
What kind of temp drops are you guys (portlandcruiser) seeing when the cooler is installed? And where do you measure?I see 250 at the pan right next to the plug after long highway grades (i70 front range) and after heavy stop and go city traffic (takes about an hr). On steep highway grades it's like it hits a wall, I can be cruising in overdrive at 70 and come up on a grade and drops speed pretty quick roms stay around 2300 but speed drops to about 45 mph. around town when it gets pretty hot it seems to slip very slightly but only from 1st to 2nd when I'm feathering the peddle, the rpms jump about 500 or so but if I have steady pressure on the peddle it seems to find the gear smoothly. Should I even worry about a trans cooler, because it's not going to fix the slipping. Or should I just start saving for a gm drive train swap?
 
I always measure the temp at the pan because it contains the oil that is actually available to the transmission.

I'm planning to install an H55F next year, but I want to take a few burly road trips before that happens. The trans cooler is cheap insurance that you can keep puttering along in the auto transmission until you're ready to upgrade the drive train. The installation itself is pretty straight forward and should cost around $100 - $150.
 
IF your A/T light comes on during a long drive you need to change the fluid immediately. Running burnt fluid is how you ruin your transmission and require a swap/rebuild.

I run a F250 cooler and SunGauge At temp gauge. I also carry a infra-red temp reader to verify temps when I jump out the truck on occasion.

When you go up grades and you should keep your truck in 4th gear. Even if that means doing 45mph up the slow truck lane with your hazards on. Running extended periods in 3rd gear will overheat your transmission. It cannot lock up in 3rd and therefore the torque converter will not lock up. Rodney from Wholesale Automatics in Australia makes an extreme valve body that allows torque converter lock up in 3rd.

RocDoc runs the extreme valve body and if I had extra cash I would upgrade too. I love the A440F slushbox. All the haters can roll up their windows manually.
 
I got the Hayden 679 installed this afternoon! Went ahead and cut off the crimped fasteners on the passenger side hose with a dremel and replaced it with the two 3/8" transmission cooler hoses:

lFjEjDI.jpg


Took it on a test drive around the neighborhood where I really gave the transmission a thrashing and no leaks / no issues. I'm feeling paranoid about the hose clamps and might add another set of redundant clamps tomorrow.

In case anyone else was wondering, here's a link to Rodney's extreme valve body that @Randy88FJ62 mentioned.
 
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I will mention. Placement is key, or atleast was for me. I started with a BIG cooler, and ended up down sizing to one smaller. The large cooler blocked too much air to the radiator, and on the highway my mechanical fan would kick on and off ALOT. Went to a smaller size on one side, havent had an issue in the past 3 years.
 
@Vulin, the one I installed is 11"X11" which I believe is on the small side. Maintaining good airflow to the radiator is definitely something I'm concerned about. I suspect I might run into engine cooling issues since I mounted the trans cooler nearly flush with the radiator.

The next real world test is going to happen on Thursday when I repeat the same drive that lead to the AT temp light going off and I'll definitely report back to this thread when I get back.
 
dffj6288 said:
What kind of temp drops are you guys (portlandcruiser) seeing when the cooler is installed? And where do you measure?I see 250 at the pan right next to the plug after long highway grades (i70 front range) and after heavy stop and go city traffic (takes about an hr). On steep highway grades it's like it hits a wall, I can be cruising in overdrive at 70 and come up on a grade and drops speed pretty quick roms stay around 2300 but speed drops to about 45 mph. around town when it gets pretty hot it seems to slip very slightly but only from 1st to 2nd when I'm feathering the peddle, the rpms jump about 500 or so but if I have steady pressure on the peddle it seems to find the gear smoothly. Should I even worry about a trans cooler, because it's not going to fix the slipping. Or should I just start saving for a gm drive train swap?
Click to expand...

I've had my cooler installed all summer and it has definitely solved the heat problem. I don't have a temperature gauge so I can't comment on the temp drops. I have run it over the passes many times this summer and the AT Temp warning has not appeared.

My trans is very sensitive to fluid level and I get the first-to-second-RPM-spike when the level is low. It's my indicator that it's time to top off the trans fluid.
 
lechnito said:
I got the Hayden 679 installed this afternoon! Went ahead and cut off the crimped fasteners on the passenger side hose with a dremel and replaced it with the two 3/8" transmission cooler hoses:

lFjEjDI.jpg


Took it on a test drive around the neighborhood where I really gave the transmission a thrashing and no leaks / no issues. I'm feeling paranoid about the hose clamps and might add another set of redundant clamps tomorrow.

In case anyone else was wondering, here's a link to Rodney's extreme valve body that @Randy88FJ62 mentioned.
Click to expand...

I'm looking to install a Hayden 679 as well but noticed that it comes with a 11/32" hose. I see you installed the 3/8" hose on the cooler. How's it working? Is it staying on? I'm a little unsure about the 3/8" as it seems to be larger than the included hose. But don't want to install a smaller hose (11/32 ") and limit the oil flow.
 
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