GX460 Transmission fluid cooler (6 Viewers)

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Is there any harm in having two coolers in series? I've added the factory cooler to mine now, but I've been thinking of acquiring a heavier trailer and I think I wouldn't mind maybe adding a Hayden 679 in series.
 
Is there any harm in having two coolers in series? I've added the factory cooler to mine now, but I've been thinking of acquiring a heavier trailer and I think I wouldn't mind maybe adding a Hayden 679 in series.

I would get the trailer and tow a few times before thinking about adding more cooling capacity. I would also probably go with one high quality cooler vs two hayden coolers. More components will always equal more changes of failure.
 
For sure, all valid points
The only advantage I see is maybe having more surface area and easier mounting options, two smaller coolers instead of one larger one.
But the introduction of more points of leaking is obviously not ideal
Thanks guys. Prolly will just swap out the factory cooler if need be
 
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It's pretty easy and cheap to swap out the factory cooler with a Hayden. I have a 678 which keeps things super-cool. You should not need any more cooling than that (unless you are towing up a really long grade in 3rd gear or lower where you don't get TC lockup, however you'll still be better off than stock). It's maybe a $100-150 mod all in. You can DIY a bracket where the Hayden will bolt up to the factory cooler mounting points, so it will look pretty clean and very factory-esque in nature (generally un-noticeable).
 
It's pretty easy and cheap to swap out the factory cooler with a Hayden. I have a 678 which keeps things super-cool. You should not need any more cooling than that (unless you are towing up a really long grade in 3rd gear or lower where you don't get TC lockup, however you'll still be better off than stock). It's maybe a $100-150 mod all in. You can DIY a bracket where the Hayden will bolt up to the factory cooler mounting points, so it will look pretty clean and very factory-esque in nature (generally un-noticeable).

Just an FYI you are posting in the GX460 forum, where 95% of the GX460's don't have aux coolers from the factory unlike the GX470, nor the the brackets or mounting locations. Just a heads up to clear up confusion.
 
Just an FYI you are posting in the GX460 forum, where 95% of the GX460's don't have aux coolers from the factory unlike the GX470, nor the the brackets or mounting locations. Just a heads up to clear up confusion.
Understood, however the most recent poster (which I was commenting to) indicated they have already added a factory cooler. In looking at photos of the GX460 factory cooler mounting (and what others have done), it's very similar to the GX470 and it would not be difficult to make a mount for a larger Hayden with some basic metal flat stock.
 
You can definitely put a larger transmission cooler in the OEM location. I had a large Tru-Cool 47391 (will not mount in OEM location) on the GX470 before I swapped it over to our LX570. Then I retrofitted the 200 series transmission cooler (which is about 2 times the size of the stock GX470/460 transmission cooler) into the OEM location for the GX470. Just go to the hardware store and get a couple of brackets or aluminum plates to fabricate your mounts.
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Bumping this up as I've secured parts to install a cooler.

A few questions though - after watching a few install videos, I still want to confirm which of the hose nipples are the outlet from the radiator. It looks like the short, J shaped hose, with fluid leaving the radiator from that port and returning to the trans from there. From what I understand, the correct routing is transmission > radiator > additional cooler > transmission.

Also - for those that used a Hayden 678, did you need to add fluid and how much? I need to flush my trans soon anyway, but don't want to run it low because the cooler is taking some fluid. Also, does the fluid drain out entirely with the cooler oriented sideways (ports to the right, facing the truck)? Might make doing a drain and fill a little more involved as it's going to read high when it's not running and pushing fluid through the cooler, right?
 
For the fluid, I'd top it off when you are done (via the FSM procedure and the fill plug on the side of your trans). It's not a particularly difficult process to do that if you have a scanguage/Bluetooth OBD2 reader to monitor trans temps, and would avoid detailed accounting of the new fluid capacity and whatever leaks out during the cooler install.

Honestly, I'd just do a full fluid exchange while you are in there anyway to avoid having to do it again in the future (with a pan drop too). You can do most of the fluid exchange via the cooler hoses that you will install for the 678. I obviously have a 470, but most of the process should be the same. Then you won't have to think about your trans for another 30-50K miles.
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Bumping this up as I've secured parts to install a cooler.

A few questions though - after watching a few install videos, I still want to confirm which of the hose nipples are the outlet from the radiator. It looks like the short, J shaped hose, with fluid leaving the radiator from that port and returning to the trans from there. From what I understand, the correct routing is transmission > radiator > additional cooler > transmission.

Also - for those that used a Hayden 678, did you need to add fluid and how much? I need to flush my trans soon anyway, but don't want to run it low because the cooler is taking some fluid. Also, does the fluid drain out entirely with the cooler oriented sideways (ports to the right, facing the truck)? Might make doing a drain and fill a little more involved as it's going to read high when it's not running and pushing fluid through the cooler, right?

I did a Hayden 678 a few weeks back and didn't lose much fluid when swapping the lines so I topped off my fluid using the odb2 pin procedure. It didn't take much. I drove it for a few weeks (not many miles since I WFH.). Then I realized the thermostat hadn't opened during the fill procedure so I pinned it open and did the procedure again and it tool almost a quart.

Here is how mine is mounted. Only needed one bracket and the horns were mounted on the middle support.

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