Can an aftermarket bumper cause excessive transmission temps?

Out of curiosity, why did you size your bracket to fit the 698 cooler rather than the larger 699 model? It looks like both would fit and as long as it was one of the thermal bypass models, wouldn't bigger=better?

The 698 size is what I originally installed on my personal FJ years ago. Its now on 39" tires with all the armor and weighs almost 6000 lbs, seems to still cool adequately.

I agree you can never have too much cooling capacity and if it were up to me every Toyota would have an aux cooler installed, a 698 is vastly better than no cooler at all.

The other reason is the 698 size is alot easier to make bolt-on brackets for.
 
I have the same bumper, but don't have the issues OP is having. I have the koyo all aluminum radiator. Though I did put a massive trans cooler in along with a heatsink type p/s cooler too. Also used foam tape to seal up the fan shroud, a/c condenser, trans cooler. So any air the fan/driving air is forced through the cooling stack. Also I did replace the ac condenser as the oem one was so corroded and plugged (air passages). It's a massively tight squeeze for the trans cooler. Had to make a custom ac line.

Cooler:
Universal Dual Pass Bar & Plate Oil Cooler, Medium | Mishimoto

Coolant temps 190 solid
Trans Temps 150-180 (high side was going up a pass).
 

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The 698 size is what I originally installed on my personal FJ years ago. Its now on 39" tires with all the armor and weighs almost 6000 lbs, seems to still cool adequately.

I agree you can never have too much cooling capacity and if it were up to me every Toyota would have an aux cooler installed, a 698 is vastly better than no cooler at all.

The other reason is the 698 size is alot easier to make bolt-on brackets for.

Thanks for sharing your thoughts on that! I've got both sizes sitting in the garage so I'm going to try getting the bigger one to work. I'll be the first time I've made custom brackets so wish me luck! :D
 
I have the same bumper, but don't have the issues OP is having. I have the koyo all aluminum radiator. Though I did put a massive trans cooler in along with a heatsink type p/s cooler too. Also used foam tape to seal up the fan shroud, a/c condenser, trans cooler. So any air the fan/driving air is forced through the cooling stack. Also I did replace the ac condenser as the oem one was so corroded and plugged (air passages). It's a massively tight squeeze for the trans cooler. Had to make a custom ac line.

Cooler:
Universal Dual Pass Bar & Plate Oil Cooler, Medium | Mishimoto

Coolant temps 190 solid
Trans Temps 150-180 (high side was going up a pass).

Oh man, I wish I'd seen your setup before I had the bumper cut to make room for the OEM hood latch support. I was thinking about doing something like yours but I couldn't see a way to make it fit. Good to know that there is a way to support the hood latch and still fit a winch.

And speaking of, great job getting that thick mishimoto cooler to fit! Seems that everyone else with our bumper can barely get a 0.75" thick cooler to fit with a winch sharing that space.
 
[MENTION=682083]Option01[/MENTION] Thanks! It was a real PITA to get everything to fit. I made 3 different variants of the hood latch support. It's 2 pieces of 1/4 solid rod and is incorporated into the cooler mount. The bottom cooler mount is rivnut mounted. As my hood would not close without a support and I'm not putting in hood pins.

I also forgot to mention I have a 1" body lift and the bumper is a non body lift as I could not get a solid answer from coastal offroad as to what dimensions were changed. I didn't want to raise the winch any higher above the frame due to the leverage effect. So I had quite a few non-standard issues during install.

1.5 inch is as thick as I could fit with everything mounted. I wanted a massive 2" thick cooler but it wouldn't fit no matter what I did. I was running a hyden 699 with an external fan, it worked, but Temps were 220 constant on freeway up a grade with od off.

I like the bumper a ton, just wish it had more cut outs on the rear vertical plate to lighten it up more and to aid in cooling if it helps.
 
[MENTION=682083]Option01[/MENTION] Thanks! It was a real PITA to get everything to fit. I made 3 different variants of the hood latch support. It's 2 pieces of 1/4 solid rod and is incorporated into the cooler mount. The bottom cooler mount is rivnut mounted. As my hood would not close without a support and I'm not putting in hood pins.

I also forgot to mention I have a 1" body lift and the bumper is a non body lift as I could not get a solid answer from coastal offroad as to what dimensions were changed. I didn't want to raise the winch any higher above the frame due to the leverage effect. So I had quite a few non-standard issues during install.

1.5 inch is as thick as I could fit with everything mounted. I wanted a massive 2" thick cooler but it wouldn't fit no matter what I did. I was running a hyden 699 with an external fan, it worked, but Temps were 220 constant on freeway up a grade with od off.

I like the bumper a ton, just wish it had more cut outs on the rear vertical plate to lighten it up more and to aid in cooling if it helps.

Oh man, I had the same kind of trouble getting my bumper sorted. I also have a 1" body lift so I selected that option when ordering but there was still a very large gap once the bumper was welded. Thankfully my welder came up with a way to raise the bumper up a bit by adding in some material at the bottom. You can see the weld lines on the pic I posted on the previous page of this thread.

Since I had such high transmission temps, I also took the bumper back and asked him to cut some holes in the back plate for better ventilation (also in that pic)

I've got a Hayden 699 sitting in my garage right now so I'm a little disappointed to hear that you were still hitting 220 consistently with that same unit. The 699 seems like a huge improvement over the stock cooler so I'm surprised you didn't get better results. Maybe I should go back to the drawing board to see if I can find another cooler with more capacity?
 
Yep I can feel you with the bumper build. I ended up using some slip on trim to fill the gap and welded a 1/2 inch tall metal piece you can see it in the 2nd pic. I use a scan gauge for trans temp, but now have a stand alone gauge for temp and oil pressure. It gets its (oem) measurements from the outlet of the trans, so it's the hottest oil measurement.

You can give the 699 a try since you have it and see where that gets you and go from there. I might end up doing what you did regarding holes cut in the bumper, although I'm not having the issues as you are. Check your ac condenser too as they are all old now and might have the fins clogged or damaged. Also try putting on some foam tape on the fan shroud to seal it against the radiator. Makes it more efficient.
 
Yep I can feel you with the bumper build. I ended up using some slip on trim to fill the gap and welded a 1/2 inch tall metal piece you can see it in the 2nd pic. I use a scan gauge for trans temp, but now have a stand alone gauge for temp and oil pressure. It gets its (oem) measurements from the outlet of the trans, so it's the hottest oil measurement.

You can give the 699 a try since you have it and see where that gets you and go from there. I might end up doing what you did regarding holes cut in the bumper, although I'm not having the issues as you are. Check your ac condenser too as they are all old now and might have the fins clogged or damaged. Also try putting on some foam tape on the fan shroud to seal it against the radiator. Makes it more efficient.

Thanks for the suggestion on the foam tape, I'll give that a shot. The radiator and AC condenser are both new since I got a pretty good smack from a guard rail after hitting some ice. That's the whole reason the new bumper was installed in the first place lol.
 
Yep I can feel you with the bumper build. I ended up using some slip on trim to fill the gap and welded a 1/2 inch tall metal piece you can see it in the 2nd pic. I use a scan gauge for trans temp, but now have a stand alone gauge for temp and oil pressure. It gets its (oem) measurements from the outlet of the trans, so it's the hottest oil measurement.

You can give the 699 a try since you have it and see where that gets you and go from there. I might end up doing what you did regarding holes cut in the bumper, although I'm not having the issues as you are. Check your ac condenser too as they are all old now and might have the fins clogged or damaged. Also try putting on some foam tape on the fan shroud to seal it against the radiator. Makes it more efficient.

So is the foam tape you're recommending just the normal foam weather stripping you can get at the hardware store or something else specifically for automotive uses?
 
Yes correct, it is the weatherstripping foam tape stuff from the hardware store. Various thicknesses. I don't recall them though. Ah that makes sense, bummer you slid on the ice.
 
So I finally got the trans cooler installed. I managed to get the larger Hayden 699 to fit which was a bit of a challenge since I wanted to leave as much room for a winch as possible and not use the hood latch support brace as an attachment point for any of the brackets (since that would have to be removed to fit a winch). I used foam tape as suggested above and I'm pretty happy with how it all turned out. Now I just need to wait for warmer weather to see how much of an overall improvement it'll make.

Thanks again to everyone who shared their thoughts on this thread :thanks:
 

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Was looking at pic you really should clearance the cutout around freon line or bend line.
Condenser flex's with body bumper rigid with frame it will rub a hole in the line.

I know it's been a while but thanks for pointing that out. After reinstalling the hood latch support bracket, the freon line had more clearance and I added some hose around that part of the line to act as a buffer for any chafing/rubbing.
 

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