Diesel Place banner

Mike L Tranny Cooler Overheating Issues...?

5.9K views 42 replies 18 participants last post by  Dozer69  
#1 ·
Of you folks who have purchased the infamous "Mike L Tranny Cooler", has it fixed the overheating problem for you in the LLY or just lowered the temps 10 degrees or so?
Anybody put this on and have their temps remain the same?

Chris
 
#3 ·
My tranny temps have dropped by at least 20*, and I have yet to see the tranny get over 200*, even while towing heavy. Engine temps are under control as well, even under fairly extreme conditions, I never have seen anything over 220*. I highly recommend this cooler and recommend you look at few others modifications as well.
 
#4 ·
My tranny temps have dropped by at least 20*, and I have yet to see the tranny get over 200*, even while towing heavy. Engine temps are under control as well, even under fairly extreme conditions, I never have seen anything over 220*. I highly recommend this cooler and recommend you look at few others modifications as well.
Were you overheating prior to the tranny cooler upgrade? Or were you running normal? Anyone here that was running around 220-230 pulling heavy loads, but now running 190-200 due to the cooler? Seems GM would develop a new cooler if it was that simple. Just need some testimonial before I drop my $ on a new cooler only to be running in the 235-245 range while towing 10k.
 
#7 ·
Indeed my question was regarding the tranny only. My truck is only 500 miles old and surely it will break in and run cooler however I can already see that running in stop and go traffic not pulling anything at all, my tranny temps are hitting 220. Not scolding by any means, but pretty damn hot for a 20 mile commute to work with an empty truck. I have not noticed anything crazy with the engine temps.....yet.
How does the tranny cooler cool better than stock? Is it bigger? Better flowing? Obviously it bolts up to the same place so air flow over the cooler can't me much better right?
 
#8 ·
Of you folks who have purchased the infamous "Mike L Tranny Cooler", has it fixed the overheating problem for you in the LLY or just lowered the temps 10 degrees or so?
Anybody put this on and have their temps remain the same?

Chris
LOL!!! I misinterpreted the first post. Yes it is effective on the tranny. Sorry. Haven't heard the term "overheating" applied to the tranny really, it seems that it doesn't "overheat" as much as it runs hotter than most would like to see. I guess GM would say the same of the engine....

:lol:

.
 
#10 ·
Bulitnv,

Sounds like you migh have a problem but I can't tell for sure because you have no info on your turck in you sig but since you said your truck only has 500 miles I am assuming it is a 2005 and also assuming you have not doen any mods yet.

You said you see trans temps of 220 in a 20 mile commute. I am assuming that you are not towing anything. If you are seeing 220 from normal driving then something is wrong. I've never seen my trans temp go higher than the mark just below 200 - even pulling my fully loaded trailer at around 10,000 pounds.
 
#11 ·
Since its new and covered under warranty, just get the temp up and take it in to show the dealer.
 
#12 ·
bulitnv

Before the cooler my trans. was 180 - 200 empty truck in town traffic.
After cooler trans.temp max of 160 same conditions.
Freeway driving no load temps were 180 before 145 after. My truck is an 04.5 LLY
 
#14 ·
my truck is an 05, no mods. My 20 mile commute is stop and go traffic the whole way. I can hit anywhere from 15-30 lights on any given trip. I haven't seen the temps over 180 in the mornings. Only in the afternoon, about 4pm, when the temps are 90+ and the traffic is more dense.
 
#15 ·
Unless you rig id puking ANY fluids dealer will tell you all systems are normal. Water can be a 1/16 of an inch from the red zone, GM says that's normal, it's in the white - same with tranny.
I've been their done that with the dealer. A huge waste of time.
 
#16 ·
I do not believe the tranny cooler is responsible for controlling or limiting engine temps, I believe other mods that I have done are helping engine temp issues. However, the tranny cooler is definitely responsible for substantially lower transmission temps! The cooler is a bit expensive, but it is great quality, fits beautifully and certainly better than the stock one. It is well worth the money!
 
#17 ·
Expensive is a pretty subjective word. When specking quality materials and things being made to tight tolerances, it cost more for the end product. The price is reasonable for a well thought out product that delivers as advertised. I would expect nothing less out of Mike.
 
#19 ·
I agree!!! I am very happy with the product and results. If I had to do it again, I would!!
 
#18 ·
I think that $450 is alot of jack, but it if cools down the tranny while I am towing my toys out to the desert, as far as I am concerned it is money well spent. I just don't want to lay out the green only to see my tranny temps stay the same.
I went spent almost $700 on a new Mag Hytec diff cover, tranny cover and "better" fluids for my 2003 f250 V10. I listened to the hype about how the extra capacity of the tranny pan would cool down the tranny 20 degreees at least. Yeh right. First trip towing with it, it got hotter than ever before. I just don't want to dump the money to be dissapointed.
When I take the truck to the dealer will my warranty be void due to the "aftermarket" tranny cooler?

Chris
 
#20 ·
funny thread. amazing, how much rationalization a 3 digit debit to the card can buy.

we are egoists afterall, despite best efforts.

I spent 50 cents on foam and cardboard, and haven't seen over 160 in a week, mt. 110 oat. the best part is my credit card is still flush. That 50 cents delivered more than advertised, I'd say..

To those not aware of it, there has been a lot uncovered in the world of cooling in the last 6 weeks. Just happens that the stock cooler does just fine if it has airflow, a foreign concept to the GM cooling engineers, till 06 that is.
 
#26 ·
funny thread. amazing, how much rationalization a 3 digit debit to the card can buy.
Not sure the neccesity for the offhanded remark. Especially coming from someone who claims to have "quantified" a cooling system re-engineer with no repeatable or controlled test data.

Based on your own fix, why is their a "difference" in the stock truck build configuraction? surely they are all built the same?

How many "overheating" trucks have you tested simultaneously in a controlled environment with repeatable results ie; load, temperature, fuel, fuel pressure, A/f ratio, alltitude, head winds, engine tune, turbo pressure, exhasut temp, coolant temp, guage calibration, etc. And where is this controlled data to back-up your "quantifiable" fixes?

This is not something that is easy or cheap if you are truly looking for the answer. You first must isolate a set of test vehicles, then isolate the parameters at which they fail, then find things that offer repeatable results under the same critera (controlled environment). But to say you have engineered a permanent fix for my overheating truck, is a stretch and an insult to my inteligence.

Mike L's cooler on the other hand, does offer a quantifiable change. It was not designed to cure our overheating LLY's, but assist in the cooling of our tranny's. It was designed to be a plug and play so that anyone with a few tools could acomplish the install. The final product does meet his criteria to help those who are looking for it.

Egoist?
 
#21 ·
Rich, who may want to remain anonymous sent me this info,

This is just the stock trans cooler on my 05 dmax. I moved it down so the bottom is just above the bumper. I only moved the bottom down 1 1/2 inches. Most of the cooler was right in the middle of the grill.I have towed two times with my 7500 LB trailer before I found this web & before I moved the cooler down. The oat was 80/ 90 the fan came on & did its job then shut off when going over the two pass. The two passes are at 3500 & I was going at 60 mph. The truck was running at 210 & trans at 190.


He can step up and explain if he wants.

I also noticed the cooler was too close to the center of the blade to get ideal air flow. Maximum flow would most likely be at the OD of the fan blade, where surface feet per minute is greatest. I assumed gm did this to get the tranny cooler heat to signal the fan's clutch sooner. I don't know if that worked for GM or not, but some one that has a hotter running trans might try this and give the group the results. I personally run the "JJ full frontal seal" that KB is talking about and I am very happy with it.
 

Attachments

#22 ·
the trans cooler on the 06 is wider and half as tall ,most of it sits lower than the bumper ,I would say most of the air comes thru the bumper vents . The more one looks at a 07 the more you see. I would love to take the top cover off and the Grille and study one side by side with a 04/05.
 
#23 ·
Having measured all the air flow parameters involved, the lowest part of the stack has 3x the airflow of that at the top, at speed. The air's source is not important, it can sometimes come from far away, only the static pressure at the specific location, that alone defines heat exchanger efficiency, when all other variables are fixed. this is also why the basis for these changes is not intuitive, and without measurement, represents a lawn dart game.

For example, at 60 mph, the static pressure at the grill top slot location is .45 inches water, and at the lowest grill point, it is 1.6 iw. This means that most of the cooling system is doing business on the lowest half, 70% of the heat rejection occuring down low.

The lowest portion is the "usual" location for a cooler for this reason. That pic, is a valid way of introducing more flow to the cooler alone, without depriving any other component (much) in the process. Adding fins, and thickness, to an already air starved stack, is a poor approach, and irresponsible unless airflow is a addressed simultaneously.
 
#24 ·
I may have a Mike L cooler for sale. The dealer can't fix my over heating problem so In two weeks they may buy my truck back. I have no need for the cooler if I buy a new truck. Highest bid gets the cooler!
 
#28 ·
Just for the record , I have had a new RAD/AIR BOX/Hood from the dealer , I went out this AM and spent 30 minutes , sealing the stack , another 30 minutes removing the splash guard and making a hose bracket and have seen more results from this than all the rest, Killerbee and RickDlance & Fingers have done more in the last few weeks for us than the almost everyone else. I know I missed a few more (sorry) But the exact reason for the Oheat thread getting out of hand was remarks like that . don't critisize until you can be constuctive , maybe this is not a controlled test , but the results are the same so far for all who have tried them . For me this is COOOOOL!!!!!
 
#29 ·
KB,

I sincerely personally appreciate all that you and others have done for this situation. I also appreciate your wit and your apology for it. Unfortunately having gone through this situation myself on my prior truck I can understand how those still having this issue can react. When you do not get any satisfaction from the manufacturer and the manufacturer gives us boiler plate responses, it does cause some of us to be a bit sensitive. I really appreciate your recent self control to keep your remarks towards the subject at hand.

That being said, can you recommend a type of foam and where to get it for sealing up the stack?

THANKS AGAIN!! :grd:
 
#31 ·
I would be more than willing to drive to a location where some controlled test could be performed. The reality is we would need multiple rigs and some outside assistance with data recorders and tech help. Having someone on hand that was very familiar with LLY components would be mandatory.

Maybe one of the vendors has a load cell dyno and the appropiate space to get it up to temp. You need to be able to duplicate and repeat the very things that are causing the problems. You also need to be compare each vehicle to themselves as well. It is very apparent their are differences from one to the other. Why and what needs to be determined.

This would not be a small undertaking and frankly would not get done in a day. If something of this caliber and seriousness was aranged, I would pay to participate.

One thing that makes me curious is the lack of input on this subject on these boards by techs. It's waaayy to quiet, but of-course this particular topic could/would be political suicide. Call me whatever, but I have been around to long to be B.S.ed.

What sucks is that this has all been done. GM has been hashing this over for the last couple of years. Time is ticking, they are counting on us chasing our tail until it runs out...or atleast most of us.
 
#36 ·
....I would pay to participate.....
Did you Kick-In for the Recorder the Group purchased?
....but I have been around to long to be B.S.ed.....
Me Too. 6 D, and 6 Y, know what I mean?
Are you an Over Heater? Have You Sealed Your Stack?

Just wondering which Page your on.

Idahofox
 
#32 ·
All I can say is don't cut off your nose. You seem smart enough to know a good thing, and waiting around in fear of next summer is not how I would want to go through life. This effort was to spite GM, you'll see i never mention it. I don't care about financial balance sheets, and shareholder equity, the bottom line. Waiting for GM is like waiting around at a dry pond, hoping it will rain soon. I dug a well, while most people were getting frustrated. And it's free to all.

I hope it helps you as well.

PS: I would seem to be suggesting I did this by myself. That is not the case. I did a lot of testing and connected a lot of dots, but there were very supportive suggestions and ideas along the way, from good minds.

In the end, after the elusive steam cloud rises, we may all be asking "why didn't I think of that" and why wouldn't GM fix such an easily fixable issue. I don't claim to know everything, and if trucks start exploding or spewing fluids all over the road, I may have to run and hide. In the meantime...stay cool...

or not
 
#33 ·
BTW, if you decide the dyno route is something you would like to pursue, I can help supervise, and will tell you just what to look for. At this point, it would be validating my conclusions, but the more the better. it is something I have wanted to do.

Just need an overheating volunteer.
 
#34 ·
Well let"s talk about Mike L cooler first,This is a diffident improvement and will solve most Tranny high temp conditions when use for the everyday and the occasional weekend puller.Now the commercial user {GVW 18,000 plus or the upgraded trans TC} will need a much improve system, We have install Two MT/MR coolers on our commercial customers LB7/LLY .These customers are scaling at 20,000 plus,The highest temps they see now are 200* in stop and go traffic or climbing the Rookies.GM drop the ball on cooling the LLY. Take a good look at the 3 Gen cummins DC has TWO coolers one mounted on the side of the engine (it works as a cooler warmer ,DC has install a bypass thermostat on on the front cooler so when temps are below 120* it will stay closed and bypass the auxiliary cooler) their is no radiator cooler, also cummins has a electronic fan,We have install a fan override switch ,When the fan override is engage the truck ramps to 1000 rpm"s when the AC Dis-engages or engine temp drops the rmp"s drop back to 700,It will Dis-engage when the speed is above 35 mph, if engine temp hits 215*the fan will engage regardless of speed, This aids in cooling for the Tranny and AC. GM did not use electronic fan technology,I think that some of the changes and comments made will work.The technology was available GM decided not to use it .
 
#35 ·
It will Dis-engage when the speed is above 35 mph, if engine temp hits 215*the fan will engage regardless of speed, This aids in cooling for the Tranny and AC. GM did not use electronic fan technology,
they do now, for 06. What you are referring to is an electro-viscous clutch

it was slated for 05, but never made it to production in time.