Does anyone know if the automatic trucks' heat exchanger could possibly stick inside and not use cooler. basically stuck on cold bypass... will be pullin it in shop tomorrow or next day to check out. just wondered if this has happened to anyone before. truck is 05 2500 4x4. i am reffering to thr unit on drivers side mounted to block back at the firewall area... .
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trans over heating...
- Thread starter LNaugle
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There is nothing in the heat exchanger to stick, it is a straight thru path. The thermostat is in the front cooler, upper right corner looking at the truck from the front.
The drain back check ball is another source of heat issues and needs to be checked.
The drain back check ball is another source of heat issues and needs to be checked.
Have two trucks doing same thing... . one is the 05 and an 06 also same symptoms... pulling small trailer such as sled trailer... . engine heats up and trans over temp light comes on... one has new fan clutch from genos and other is still stock... . 05 has new trans and 06 is stock... no codes for fan speed... i was thinking the trans drain back deal was in the heat exchanger... ???? 05 swowing up today, checking codes and trans fluid first.
Check ball is in the cooler output line under the driver side battery.
The thermostat in the front cooler is the source of a lot of these problems, especially if the trans has been burned up or failed at some point.
Do NOT trsut the trans over temp light on the dash, it reads off the gov pressure transducer and is frequently the source of problems. Always verify the temp with an analog gauge.
Not sure what you mean by the engine heats up, is it over temping or just warm? If the flow is reduced in the cooler system it won't transfer or pick up as much heat from the engine but will generate more internally. Again, you need to see atucal temps out of the trans to verify.
A trans temp light can also be triggered by fluid leaking into the trans control harness plug.
The thermostat in the front cooler is the source of a lot of these problems, especially if the trans has been burned up or failed at some point.
Do NOT trsut the trans over temp light on the dash, it reads off the gov pressure transducer and is frequently the source of problems. Always verify the temp with an analog gauge.
Not sure what you mean by the engine heats up, is it over temping or just warm? If the flow is reduced in the cooler system it won't transfer or pick up as much heat from the engine but will generate more internally. Again, you need to see atucal temps out of the trans to verify.
A trans temp light can also be triggered by fluid leaking into the trans control harness plug.
Yes it can be removed and cleaned up.
You need to disconnect and pull the AC condensor out of the way and remove the CAC to get to the cooler.
Once you can get to the block in the upper right corner there is a c-clip that holds the sealing washer in the end, remove it.
Take a butane torch and slowly heat the aluminum block and the sealing washer will pop out. The thermostat and pieces can then be removed and cleaned up. Keep track of how the pieces come out and just re-assemble in reverse.
Make sure you catch the pieces as they are under spring pressure and may fly around as the heating releases the sealing washer.
The caveat is the sealing o-ring. If it looks at all bad you will need a new one or it will just puke fluid all over the place. Needs to be a special one to hold the fluid. Not any o-ring will work.
Would there be adverse reasons to just take out the inside parts, leave them out for constant fluid flow (thermostat and or check valve ball).
I see temps around town, stop and go, crawling around the woods at 190 to 225. Now towing and or hwy I see 170 to 180 constant but it will heat up to 200'sh when I stop at a long stop light. When the convertor locks the temp always reduces 10-15 degrees.
I just want to do the best for the heat to get rid of it as I to believe the heat over a long time will be detrimental to teh transmission's life
I see temps around town, stop and go, crawling around the woods at 190 to 225. Now towing and or hwy I see 170 to 180 constant but it will heat up to 200'sh when I stop at a long stop light. When the convertor locks the temp always reduces 10-15 degrees.
I just want to do the best for the heat to get rid of it as I to believe the heat over a long time will be detrimental to teh transmission's life
The thermostat in the cooler is designed to bypass the main cooler body until the temp is over 140 degrees. Removing the pieces would just open the bypass to a constant flow. Fluid is going to take the easiest path and bypass the main cooler leading to higher temps.
The dodge Engineers pretty much confirmed the optimal operating temp range of the transmission is 140-240 degrees. As long as you are in that range and change the fluid on the reccommended basis you should be good. The rating on the fluid is considerably higher so the only consideration would be on the clutches and seals.
There is only so much you can do about fludi temp generated in the TC. That is a function of load and use. In low speed heavy load conditions it will frequently just get that warm from the TC churning the fluid.
If those situations where there is low air flow drive the overall trans temps up a aux cooler with a thermstat activated fan can be added to help the return fluid cool down. This is a bit of a catch22 because the cooler return flow is used to cool and lube the transmission hard parts. Adding extra restriction to a system that relies on the flow for important functions can end being detrimental.
As a rule, if you want better cooling removing the drain back check ball and adding a shift kit to raise the line pressures and circulate in park is a good start. If that is still not enough, the aux cooler can be added. With the higher line pressures supplying cooler flow extra restriction tends to become less important.
Even engine rpms driving can help the cooling. The stock system doesn't max its pressures out until over 2000 rpms whereas most of the shift kits have maxxed by about 1600 rpms. Extended operations at low rpm is tough on heat disipation. Simply downshifting will help circulation to a point it can be noticed.
The dodge Engineers pretty much confirmed the optimal operating temp range of the transmission is 140-240 degrees. As long as you are in that range and change the fluid on the reccommended basis you should be good. The rating on the fluid is considerably higher so the only consideration would be on the clutches and seals.
There is only so much you can do about fludi temp generated in the TC. That is a function of load and use. In low speed heavy load conditions it will frequently just get that warm from the TC churning the fluid.
If those situations where there is low air flow drive the overall trans temps up a aux cooler with a thermstat activated fan can be added to help the return fluid cool down. This is a bit of a catch22 because the cooler return flow is used to cool and lube the transmission hard parts. Adding extra restriction to a system that relies on the flow for important functions can end being detrimental.
As a rule, if you want better cooling removing the drain back check ball and adding a shift kit to raise the line pressures and circulate in park is a good start. If that is still not enough, the aux cooler can be added. With the higher line pressures supplying cooler flow extra restriction tends to become less important.
Even engine rpms driving can help the cooling. The stock system doesn't max its pressures out until over 2000 rpms whereas most of the shift kits have maxxed by about 1600 rpms. Extended operations at low rpm is tough on heat disipation. Simply downshifting will help circulation to a point it can be noticed.
Thanks for the info, which shift kit do you recommend? I remember that some are reversible and some are not, just want good quality kit.
I'm not mechanically inclined, but our mechanic at my work is a master ASE certified he should be able to do this IMO.
I see on another forum where they cleaned the tstat, do they get that dirty to need cleaning? I'm worried about after its cleaned and the install back that it may leak because of the heating procedure.
I only have 75,000 miles on my 2006
I'm not mechanically inclined, but our mechanic at my work is a master ASE certified he should be able to do this IMO.
I see on another forum where they cleaned the tstat, do they get that dirty to need cleaning? I'm worried about after its cleaned and the install back that it may leak because of the heating procedure.
I only have 75,000 miles on my 2006
The Superior shift kit seems to the choice for ease of install and doing what needs done. You can back to stock from it where the TransGo you cannot.
Heating the block needs to be done carefully because the oring can suffer if it gets too warm. The aluminum will expand quit fast so care has to be taken. The only problems I am aware of after doing this is the o-ring. Normally it should not be an issue but every one is different.
If you have ever burned a trans or had one fail its a good chance the thermostat can get sticky. If not then it is unlikely. With 75k and no problems it is not a usual problem unless you can verify the cooler shows much less heat in the body than the bypass tube.
The drain back check ball is a worse restriction. Removing it and adding a shift kit may be all that is needed. Check your cooler carefully and make sure it is not leaking also. If you are seeing nay leaks replacement with a Derale unit or another one with a thermostat may be more useful.
Heating the block needs to be done carefully because the oring can suffer if it gets too warm. The aluminum will expand quit fast so care has to be taken. The only problems I am aware of after doing this is the o-ring. Normally it should not be an issue but every one is different.
If you have ever burned a trans or had one fail its a good chance the thermostat can get sticky. If not then it is unlikely. With 75k and no problems it is not a usual problem unless you can verify the cooler shows much less heat in the body than the bypass tube.
The drain back check ball is a worse restriction. Removing it and adding a shift kit may be all that is needed. Check your cooler carefully and make sure it is not leaking also. If you are seeing nay leaks replacement with a Derale unit or another one with a thermostat may be more useful.
That will help. Just understand the line pressures will be basically stock unless you get different springs for the PR valve. A shift kit contains the springs, check balls, seperator plate, etc, that makes it a shift kit.
If you use the Sonnax valve then don't make the modifications some kits suggest for TC charge in park. There are different ways to achieve that and you have to know how the kit is doing it so you don't mess up other operations.
i removed the t-stat in the trans cooler and blocked the bypass line off so i am running all the fluid thru the cooler all the time. (Also removed the drainback check ball from the output line. ) I have no problems with the trans getting warm enough with this setup but i also live in oklahoma so we rarely see really cold temps and the one time we did since i made the modification i just put a piece of cardboard behind the grill and all was good.
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Issue 128 – Digital Version
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