randeez
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it just didnt keep temps as cool as the 40k in the grill, both installed with radiator also in line. i pulled the fans off of the derale and installed it in the grill so i'll see how it does
Aux Trans Cooler with Fan OPTIONS
- Thread starter Foggy
- Start date
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it just didnt keep temps as cool as the 40k in the grill, both installed with radiator also in line. i pulled the fans off of the derale and installed it in the grill so i'll see how it does
Tim907356
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I don’t have a problem with the hardware; the online shop I bought from was/is a nightmare; Five Star Transmissions. They messed up the order with flare!
I took it to the shop to ha e diagnostics done and a filter change after the cooler install. They said the torque converter is going out. It causes the ‘stumble’, or flutter coming off idle rpm, to a load. He said it’s typical with these because they’re never locked in, but always slipping. So it makes me wonder if the coolers are needed if the torque converter is working properly. Can’t hurt to have it...what will hurt is a new $1800 torque converter - OUCH!
I took it to the shop to ha e diagnostics done and a filter change after the cooler install. They said the torque converter is going out. It causes the ‘stumble’, or flutter coming off idle rpm, to a load. He said it’s typical with these because they’re never locked in, but always slipping. So it makes me wonder if the coolers are needed if the torque converter is working properly. Can’t hurt to have it...what will hurt is a new $1800 torque converter - OUCH!
Definitely if your torque converter is NOT locking up properly, it will create LOTS of heat
It's like having a high stall converter at that point.
Our trans' have a way to lock up the clutch in stages and/or as a percentage.
IF you ever saw the lock up clutch in your torque converter in a 6L80E, You'd
wonder how it ever stayed together "this long".. IT's Tiny...
You don't need a billet or a higher stall or a performance converter, but we
all need an "upgraded unit" that has a larger clutch apply area.. That's the key.
And when the clutch material lets go, it spews all that trash into the rest of the trans
So, my advice, if you have a trustworthy shop: spend an extra $500-800 when the
trans is out for the converter job and upgrade the "known" weak points of the
trans itself
And do some research to find a quality reman converter: using the oem GM core
is absolutely fine and it's design is fine other than the clutch being too small
tmt502
Member
I found this thread and I've been thinking about the need to install a trans cooler on my rig. After doing a fluid and filter change about a month ago, I've towed the boat enough times in 85 to 95 degree weather to see that my fluid temps are hovering around 200 and up to 212 when towing. Since my truck didn't come factory equipped with the cooler, my questions are:
Is this going to be a difficult retrofit?
Will I encounter major issues while doing this (should it be done by a shop)?
Best recommendations for a unit that will fit in the 'stock' location?
Is this going to be a difficult retrofit?
Will I encounter major issues while doing this (should it be done by a shop)?
Best recommendations for a unit that will fit in the 'stock' location?
If you are Towing in 90* weather and your trans temps are around 205* Ish,
then you are just fine.. I wouldn't bother with an additional cooler. That's normal
temps.. Now if you run over 200 not towing, then I'd be concerned
tmt502
Member
Thanks for the input! I was actually just out running an errand a few minutes ago, not towing. It's about 95 here today. Trans temp was showing 201 in some stop and go conditions.
I like the spec's on your rig....
Thanks !! I'm still trying to get it to run perfectly.. The dyno tune shop I used
wasn't very good.. It runs fine, but my MPG went in half while towing and I went
from 17-18 mph highway cruise control down to 13.. So I'm thinking I need
to buy the HP tuners and just do it myself !!
I really built it for towing and strength. I have a 32" travel trailer that
weighs about 8K and we want to travel a bit whenever possible and we
have 2 big dogs-shepherds. So a pickup just wasn't working anymore.
Tim907356
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That's why we upgraded to the Denali aslo. We pull a 24' now, and want to upgrade to a ~30', probably around 9k. I was surprised to find issues with the tranny, as the 6sp was recommended for better towing than the 4sp in my 2004 Yukon XL, 5.3L. We put 20K worth of towing miles on that vehicle and never had a lick of trouble out of the power train, and we conquered some major hills! The Denali definitely has more gitty-up, but the tranny issues are now making me nervous...and as you know, are way more $$ to fix than the old 4sp.
At 9000 lbs , you will def have to do some mods to the denali to keep it together and
tow safely. I still have to replace my G80 differential. I've got the TruTrac, but haven't
had the time to put it in yet due to surgery. I did the Timbren bumpstops and added
air bags to the rear coils. I was even thinking of "downsizing" to a little smaller
trailer. Ours is a High Country with 3 slides: advertised to be 1/2 ton towable , my ass !!!
I've been towing it with my 1994 Stepside C1500 for the last several years, but It
is highly modified with a SC'd 422 ci SB Chevy, built 4L80E and Ford 9" Rear end & Big ass brakes and Suspension
I also runs mid 11's with some drag radials !! I'm glad I get to take it out of
tow duty mode.. It was white knuckle driving even with all the mods
I would def shop for a trailer that's under 8K GROSS, which would be about 6K empty
or "shipping" weight. you have the advantage now to buy a trailer that works best for
your vehicle.. Remember, you'll have lots of stuff in the Yukon too
I like having more interior space, although I do miss the PU Bed for
wood, trash, grills, etc
thompsoj22
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Just an update on the DERALE 13960 25 row stacked plate with aux fan, It works! Just got back from mammoth towing the TT at 4400 lbs loaded. The grade from bishop to crowley is 6% 8 miles long, outside air temp was 98f. The aux cooler is mounted under the bumper with the lower fascia modified for ram air. The radiator is still in the circuit and is a detriment without a doubt but the cooler can overcome the affect of the radiator coolant temp increase on the trans fluid. The thermostat on the cooler turns the fan on at 180f and off at 165f, the trans was running at 176 until we hit some small grades and rose to 187, The cooler aux fan turned on and did not turn off for the next 150 miles keeping the trans in the 170f range until we hit the grade where we crested the top at 189f in 4th at 3100 rpm!!! This grade with the factory cooler drove the trans to 238F and had we not been at the top i would have had to pull over as it seemed that it would have continued to get hotter. Positives, It works, It removes the trans heat from the ac condenser/engine compartment and absolutely is big enough to control the trans temp in brutal summer heat while towing. Negative, Only the fact that there are line connections/fittings and each one has the potential to loosen and leak with the potential of destroying the trans. I like this setup enough to pull the front fascia, remove all the an fittings and drill them for safety wire and locktight them on the final cleanup.
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