2012 LML I had the trans rebuilt by copperhead diesel performance. However with the rebuild it has more line pressure causing more heat. I have 37s not towing and after a 15 min drive my trans temp is 190, I live in Arizona ambient temp is 115 pretty much all the time. It’s causing hard shifts into converter lock when it’s hot. Is there a good upgraded trans cooler available? I still have the stock cooler and I was told that it’s not in the “danger zone” so don’t worry about it but no one else I know has this issue I’ve seen the PPE bar and plate cooler does it work well? Should I add a switched 800 cfm cooling fan? Any advice would be appreciated!
ISO upgraded LML trans cooler
- Thread starter ChaseTimmick
- Start date
No your temps aren't high, but to me that's high for such a short drive. I'd suspect they didn't flush the cooler properly during overhaul
So do you think buying a mishimoto or Ppe cooler would be worth it
Remember the engine radiator shares a cooler with the transmission. This will cause heat from the engine to heat the transmission fluid until the transmission and engine are about the same temperature. Having the transmission at or near the engine temperature is normal
It might help, but I'd make sure the coolers were hot flushed first. Like I said, temps aren't abnormal but that seems excessive for a 15min drive
Coolant temp sticks around 185
So the stock cooler should be able to keep up with the higher pressure?
Per the dash or a scanner?
My dash doesn’t show exact but the gauge sits right below 210 and scanner gives me exact temps when I switch to tow haul to help drop the trans temp my coolant temp gets to 190-195
There's a couple guys that live down in AZ, maybe they'll chime in. If it gets to 200F but stays there that's fine, to me that is climbing a little fast but 20min in stop n go traffic I could see that. 20min cruising, no.
Depending on how the transmission was setup when built, and if they bypassed the EPC, you could benefit from a transmission tune that still utilizes the EPC to drop pressures when at low throttle. 200F should not be causing hard shifts though
Depending on how the transmission was setup when built, and if they bypassed the EPC, you could benefit from a transmission tune that still utilizes the EPC to drop pressures when at low throttle. 200F should not be causing hard shifts though
Sean at copperhead is good friend of mine. He does not build crap transmissions, only does a few a year because he does not want to be known for transmissions, just diesel work and knows his stuff on them. He does use a hot flush on the trans coolers and uses goerend converters. Hes on the opposite side of town from me but we talk and share stuff all the time. Im just putting that out there before we go jumping off the “blame the builder” bridge.
You are absolutely fine. That is 100% common. 100* over ambient is to be expected here and yes, even after 20-30min. You will see higher in traffic and 110-120* heat because the asphault super heats the air and is closer to 140-150* air temp at 3-5pm. Mine will run 210-220* even with a setrab cooler but im running 330psi line pressure
What size build did you go with? You most likely have an epc blocker inside and im sure he verified with you that you do NOT have tcm tuning for pressures.
Can you add a cooler? Absolutely. Do i think you have an issue? Nope. Converter lock up is going to be aggressive. Again, part of that can be due to the build you chose too
You are absolutely fine. That is 100% common. 100* over ambient is to be expected here and yes, even after 20-30min. You will see higher in traffic and 110-120* heat because the asphault super heats the air and is closer to 140-150* air temp at 3-5pm. Mine will run 210-220* even with a setrab cooler but im running 330psi line pressure
What size build did you go with? You most likely have an epc blocker inside and im sure he verified with you that you do NOT have tcm tuning for pressures.
Can you add a cooler? Absolutely. Do i think you have an issue? Nope. Converter lock up is going to be aggressive. Again, part of that can be due to the build you chose too
I’m not blaming anyone I love the trans and the guys at copperhead are great I have no complaints. I’m giving all the information I have so that I can get accurate info back. It is heat related the hard shifts into converter lock do not start until it gets over 195 prior to that I have no issues at all. I have all the receipts that I can get all the details from but it’s 750 ho capable triple billet disk converter
I just added the PPE plate and frame trans
cooler because I preferred to live on the cooler side. I’d say I was running similar temps when in stop & go traffic (also in Phoenix, FYI)…I got up to 210 once with the stock cooler. My understanding is roughly 225 is the danger zone, or anything north of 230 can actually void a warranty (depending on the builder). So I decided to install the PPE Plate and Frame transcooler, took 30-45 minutes to do, but already had the -AN adapters so it was plug and play. It has knocked my temps down to 175 in stop and go, hits 180-185 every once in a while if I’m on it having some fun.
Chevy1925 knows what he’s talking about, so no doubt it is likely not a necessity. If $300-400 bucks is worth it to you, then it can’t be a “bad” update. I’ve been educated by several folks that heat is one of the biggest killers for a diesel transmission. To me it was worth the peace of mind, just sharing my thoughts. Hopefully useful. See the picture below, for example.
cooler because I preferred to live on the cooler side. I’d say I was running similar temps when in stop & go traffic (also in Phoenix, FYI)…I got up to 210 once with the stock cooler. My understanding is roughly 225 is the danger zone, or anything north of 230 can actually void a warranty (depending on the builder). So I decided to install the PPE Plate and Frame transcooler, took 30-45 minutes to do, but already had the -AN adapters so it was plug and play. It has knocked my temps down to 175 in stop and go, hits 180-185 every once in a while if I’m on it having some fun.
Chevy1925 knows what he’s talking about, so no doubt it is likely not a necessity. If $300-400 bucks is worth it to you, then it can’t be a “bad” update. I’ve been educated by several folks that heat is one of the biggest killers for a diesel transmission. To me it was worth the peace of mind, just sharing my thoughts. Hopefully useful. See the picture below, for example.
230 is not a danger zone. 230 will cook trans fluid quicker than 200 though. The older medium duty tow trucks with allison 1000’s run 230* trans temp day in and day out. They kill hard parts before clutches but thats not fluid related.
Mike always told me, truck should be around the 100-110* above ambient on a stock cooler. If you are sticking to that temp, all is well. You start running well above that constantly, we got a cooler issue. So 230* in traffic in 120* weather is a non issue. The facebook know it alls blow trans temps out of proportion because they are use to the knock down pressures the LML and up have that keep temps lower.
Ive towed at 225* for a few hours, no problem in my 02. Should watch my 2020 10 speed trans temp run up to 220-230 when im pulling my toy hauler in the white mountains. 1st gear, creeping along shitty wash board roads, up hill for over an hour makes that trans temps climb. I change that fluid every 30k though
Mike always told me, truck should be around the 100-110* above ambient on a stock cooler. If you are sticking to that temp, all is well. You start running well above that constantly, we got a cooler issue. So 230* in traffic in 120* weather is a non issue. The facebook know it alls blow trans temps out of proportion because they are use to the knock down pressures the LML and up have that keep temps lower.
Ive towed at 225* for a few hours, no problem in my 02. Should watch my 2020 10 speed trans temp run up to 220-230 when im pulling my toy hauler in the white mountains. 1st gear, creeping along shitty wash board roads, up hill for over an hour makes that trans temps climb. I change that fluid every 30k though
Bingo, especially the bolded segment!
100-110F over ambient is absolutely normal. Now, that said, if you want to drop temps a cooler is not at all a bad purchase. I've gravitated toward the Mishimoto and Fluidyne coolers after having a few PPE bar and plate coolers leak on customers.
Also, James is 100% correct again on fluid temps and what they do to fluid. Every fluid will handle heat and degrade differently due to it's base stock and additive package. More expensive fluids tend to handle temp better as they're made from higher quality ingredients.