about to do the instal in the morning with a temp sensor...which line is the output and which is the return? is the one going into the pan( or farther back on the trans) the return?

Thanks!!

 

If you look at where the cooler lines go into the radiator cooler.The shorter one to the radiator(passenger side) is the output to the radiator cooler...The longer one that runs along side the radiator to the radiator cooler is the return(driver's side)(drops fluid back into trans pan).....This holds true for all Factory Toyota's set-up w/ radiator cooler..........If say you are woring on something else..all you have to do is unhook a line,put a catch pan underneith..have someone start the vehical and see which way the fluid flows and have them shut it down as soon as the fluid flows.

 

Can you plug the factory cooler with a NPT fitting?

If so, what size is it?

It not, what is the size/thread pitch of the cooler.

(I would rather plug it than connect them with a hose.)

 

They are no doubt metric fittings. Just pull out one of the hose barbs on the radiator, and measure it. What's your objection to connecting the two with a hose?

 

Well, I put an order in for an Isspro Trans oil temp gauge and sender (Part: R5659R), a Tru-cool tranny cooler (Part: 4454) and a thermal bypass (part: 708-4739). I'm expecting it in late this week. I'm going to try to do the install of the temperature gauge either during this weekend or some night next week. I want to get some baseline temperature data with the stock cooler (and the small aux cooler that I currently have in series with the stock one) before I install the new tranny cooler and bypass the stock one.

 

Good idea

 

Well, I installed my tranny temperature gauge today. I don't have pictures yet, because I just finished up and it's midnight. I'll try to snap a couple of pictures this week. I just wanted to post up a bit of preliminary data before I forget.

My current setup is: out from tranny, to tranny temp sender for my gauge, to tranny cooler in rad, to small aux tranny cooler, and back to the tranny pan. I took the truck for a quick drive tonight just to test the gauge. The ambient temperature outside was 40 deg F at the time of the test drive. My driving pattern was 10 minutes at 45 mph, then on to the highway for 10 minutes at 75 mph, then another 5 minutes at 45 mph, followed by 10 minutes at 25 mph in L gear (3200-3500 rpm).

At first, I thought something was wrong, because the gauge wasn't moving. Actually, it didn't move at all until I came off the highway and slowed back down to 45 mph. During the 5 minute drive at 45 mph, the gauge climbed to approx 130 deg F, and that's where it stayed for the rest of the drive.

I will try to get some baseline numbers with the stock setup (I'll remove the small aux tranny cooler that I am currently running in series with the stock cooler in the rad), then of course I'll also get some data after I bypass the stock cooler and install my new tru-cool aux cooler.

 

Some more data. Same setup still with stock cooler and my small aux tranny cooler in series.

Ambient temperature this morning was 35 deg F (I thought spring was here, but apparently not.) Driving pattern was 5 minutes at 45 miles per hour, idling in Park for 5 minutes, another 5 minutes at 45 miles per hour, 5 minutes at 75 miles per hour, then 5 minutes at 45 miles per hour. Same as last night, gauge didn't move at all until after I came off the highway and slowed back down to 45 miles per hour (20 minutes after I started the truck.) During the last 5 minute trek at 45 miles per hour, the gauge reached 145 deg F.

To those of you that have tranny temperature gauge sender installed near the front of the truck spliced into the rubber tranny cooler lines, do you have the sender insulated or wrapped in anything to prevent cold air from cooling it off when you're driving? My sender is mounted in a 3/8" threaded plumbing "T", which is quite thick, so it probably acts as a heat sink until the metal is eventually brought up to the temperature of the fluid.

 

My sensor isn't wrapped.

 

Well, here are a few pics of the temperature guage in it's new home. I had to fab a bracket for it, but I found a use for that useless little cubby hole, finally.





Here are a couple of pics of the sender (and the sender block that I made). The sender is installed on the output line from the transmission to get the hottest temperature.

 

Nice! You got the green bulb covers didn't ya.

 

Yes I did. Only a couple of dollars, and it matches the rest of my dash lights.

 

Goat and GS,

Thank you for continuing to keep this thread alive with great info! My 'thank you' is way overdue as I have been following this thread all along and have picked up a ton of useful info!

My thermal bypass just arrived today - I will probably install it this weekend and bypass my radiator. I just broke 100,000 miles and figure I am probably on borrowed time as far as the 'strawberry shake' syndrome goes. I live in So Cal (mild weather), but might do more winter traveling like we did to Utah this past Christmas, so I figured it would be better if I went with the thermal bypass.

I might go with a temp gauge later - I wanted to keep it as simple as I could, especially knowing that my install would probably be a far cry from the slick install GS just did.

Thank you, again!

Steve.

 

No problem. I'll update with more data of the stock setup (I'll remove the small aux cooler I have in series with the stock one), then I'll update again when I bypass the stock cooler and install my thermal bypass and new aux tranny cooler.

Like I mentioned above, I bought the thermal bypass, because our winters are quite cold here in Eastern Canada. I couldn't find very much info on the thermal bypass as far as how it functions exactly. I know it is open fully at 180 deg F, but I'm wondering what temperature it starts to open at? I assume that it doesn't go from fully closed (or in bypass mode) to fully open at 180 deg F.

To those of you that have the thermal bypass installed (and a temperature gauge on the "hot" tranny line coming out of the tranny), does the fluid temperature stay around 180 deg F, or is it maintained lower than that (unless you're pushing your tranny hard, of course)? Reason I ask is that my current setup keeps my tranny fluid temperature around 150 deg F (when it is roughly 60 deg F outside). I'd hate to "upgrade" to a system that increases my normal running temperature.

 

I have mentioned earlier about my factory BMW ATF cooler not going through the radiator. Its actually in front of the radiator, behind the AC condensor. I just found a good diagram of it and doctored it up some to show the ATF flow path and built-in cooler bypass. Not sure what the thing is inline on the bypass line though, its possible its a thermostatic valve of some type but it looks a little small for that to me. If it is a thermo valve it would close or restrict flow when hot to force more ATF through the cooling fins.

One thing I'd like to point out on this flow path is the up direction (against gravity) is made while the ATF is hot and still in one tube. I believe this is to decrease the pressure losses going through the cooler system. I'd recommend setting up any cooler following this example.

 

Well, I had big plans to get data with various tranny cooler setups, but had no time this past week to remove my old aux cooler to collect temperature data with just the stock cooler.

I had the day off today, so I installed my new aux tranny cooler (Tru-Cool Part: 4454) and a remote thermal bypass (Tru-Cool Part: 708-4739), and I totally bypassed the stock cooler in the radiator. I didn't take any pictures, because there's nothing special about the install. It looks the same as everybody elses. I used the supplied brackets and bolted it in front of the A/C condenser. I haven't driven around with it much so far, but I did go for a 10 minute drive on the highway. Temperatures were pretty much the same as they were with the stock cooler + old aux tranny cooler in series. I saw a max of approx 140 deg F, and the ambient temperature outside was approx 60 deg F.

The good thing is, I got my answer about the remote thermal bypass. It does not stay fully open until the temperature gets to 180 deg F. In other words, it doesn't try to maintain a temperature of 180 deg F, but if the temperature gets to 180 deg F, at that point, the bypass would be fully closed to drive all the flow to the cooler.

 

Another bit of data here after some minor towing. It wasn't a very big load at all... the trailer probably weighs maybe 300lbs (just a guess... not sure, it's a 4ft by 8ft trailer with 1/8" metal angle frame and plywood deck). I had probably an additional 200lb on the trailer.

Ambient temperature was 60 deg F. Mostly slow driving (40 - 50 miles per hour) with lots of small hills and lots of bumps which caused lots of slowing down / accelerating. Total duration of drive was approximately 1/2 hour in these conditions. Tranny temperature reached approx 180 deg F.

 

My Tundra comes with a factory aux cooler but what brand is it? I'm planning to bypass the rad cooler too so it would pipe into the factory aux cooler. Those Long coolers have some sort of bypass in them which negates the use of a trans cooler bypass.

 

What is the point of installing a remote bypass when the 4454 cooler has the bypass built in. I also live in NB and the cold concerns me.
I need to do this mod soon and I would like to know if just installing the 4454 cooler is enough?

 

The 4454 has a built in bypass, but it is based on fluid viscosity (which is based on fluid temperature). Although a lot of the fluid probably goes through the bypass when it's cold, not all of it would. The remote bypass is recommended by Long (Tru-Cool) when their aux tranny coolers will be used in temperatures below 32 degrees F.

Where in NB do you live, 954rrmike?