Brand new (maybe not new after all) TBV 70⁰ strange temps.

[UsualSuspect]

I picked up a 2019 LD with 16k on the clock, thankfully still under the 5/100k power train warranty. I complained about surging and high temps 200+. The dealer said they couldn't duplicate it, wouldn't change it unless I wanted to pay for it, and they fought for me trying to get it approved, but the area rep said no. GM trying a save $60 in parts, and maybe $100-$200 in labor last week, is now costing them a transmission. The area Rep had to approve the replacement, now the wait for the tranny, I am not sure if it will be a reman or a new one. Either way, that was one expensive TBV for GM.

[mikeyk101]

3 hours ago, UsualSuspect said:

The area Rep had to approve the replacement, now the wait for the tranny, I am not sure if it will be a reman or a new one. Either way, that was one expensive TBV for GM.

I am fairly certain that it will be a remanufactured trans. I don't think I have ever heard of a new trans being installed to replace a failed one. But the reman is supposed to be all new internal parts so basically brand new. On the plus side, the reman trans will come with a 3 year/100,000 mile warranty.

 

IMHO, the OEM 194⁰ TBV is only part of the problem. The bigger problem is the torque converter used on these transmissions. They have a habit of grenading and then shavings end up inside of the trans, killing it. Even by going with the new TBV, the torque converter remains the same and can fail again. A buddy of mine had 4 fail within a year and finally had enough and traded up to a newer Chevy Duramax diesel. 

 

I have been told that the best upgrade is to ditch the OEM torque converter and have a newer aftermarket billet torque converter installed. If you search in the forum, you will find recommended ones. I'm still considering that option on mine.

[Grumpy Bear]

After reading this entire thread I ask some questions. Was the cooler back flushed when the transmission was installed?  Have you gone over every inch of hose to assure it is kink free? Have you checked the fluid level? I see you already checked the fins, good. 

 

Now having asked that, every transmission will have its own personality. No matter how identical we think they are or believe they should be, the factory tolerances vary and will add or subtract from its sum. It stands no better chance of duplicating the exact same experience as would a new motor duplicate the exact same fuel economy.

 

Yours behaves much like mine and while I have a different cooling setup and torque converter style the transmissions are pretty much identical. On hot days in broken traffic, it creeps right up there. Stalled in traffic all bets are off. No air moving kills cooling. Especially so for the V8 setups of later years that do not have an in-radiator liquid-to-liquid exchanger before the condenser cooler. 

 

In those low speed, stalled traffic, hot day situations have your tried AC on max cool? It runs both fans much sooner and this works on my 2015 at around 190 F water. In fact mine will kick on when it's started from cold with the AC on max recycle. 

 

Your next step if all checks and double checks is more cooler second in series with the one you have and yes, a billet converter. Not only will you get a reliable mechanical device these have stators and rotors that are furnace brazed. This means the normal fluid internal leakage at those junctures is closed and it does help lower the temperature of the fluid a bit. 

 

IF more cooler isn't your cup O' tea or even if it is, then switch fluid to either Red Line D6 or AMSOIL ATF and change it bit more often. Both are PAO based and have more heat tolerance and a slightly better thermal capacity and conductivity that the Group III ACDelco Full Synthetic. 

 

Under 170 F as a routine will give a long life. 160F is better yes. Occasional trips over 180 in situational driving is to be expected. It's the constant over 170 F that is to be avoided. My 2 cents. 

 

 

 

 

 

 

[mikeyk101]

26 minutes ago, Grumpy Bear said:

After reading this entire thread I ask some questions. Was the cooler back flushed when the transmission was installed? 

 

I was told that it was. That was one of the first questions I asked them when picking it up.

 

26 minutes ago, Grumpy Bear said:

 

Have you gone over every inch of hose to assure it is kink free?

 

Yes, everything looked fine. I was able to check the rear part of hoses when I did the pill flip and front when checking/cleaning the fins.

 

26 minutes ago, Grumpy Bear said:

 

Have you checked the fluid level? I see you already checked the fins, good. 

 

 

Yes, it was a tad low when checked hot one day after getting back home from the dealer so a bit was added. Didn't seem to really make a difference.

 

26 minutes ago, Grumpy Bear said:

 

Now having asked that, every transmission will have its own personality. No matter how identical we think they are or believe they should be, the factory tolerances vary and will add or subtract from its sum. It stands no better chance of duplicating the exact same experience as would a new motor duplicate the exact same fuel economy.

 

Yours behaves much like mine and while I have a different cooling setup and torque converter style the transmissions are pretty much identical. On hot days in broken traffic, it creeps right up there. Stalled in traffic all bets are off. No air moving kills cooling. Especially so for the V8 setups of later years that do not have an in-radiator liquid-to-liquid exchanger before the condenser cooler. 

 

In those low speed, stalled traffic, hot day situations have your tried AC on max cool? It runs both fans much sooner and this works on my 2015 at around 190 F water. In fact mine will kick on when it's started from cold with the AC on max recycle. 

 

Your next step if all checks and double checks is more cooler second in series with the one you have and yes, a billet converter. Not only will you get a reliable mechanical device these have stators and rotors that are furnace brazed. This means the normal fluid internal leakage at those junctures is closed and it does help lower the temperature of the fluid a bit. 

 

IF more cooler isn't your cup O' tea or even if it is, then switch fluid to either Red Line D6 or AMSOIL ATF and change it bit more often. Both are PAO based and have more heat tolerance and a slightly better thermal capacity and conductivity that the Group III ACDelco Full Synthetic. 

 

Under 170 F as a routine will give a long life. 160F is better yes. Occasional trips over 180 in situational driving is to be expected. It's the constant over 170 F that is to be avoided. My 2 cents. 

 

 

 

 

 

 

 

 

Good tip on the A/C max LO temp. I have not tried that yet. Very rarely have I had to run A/C on max as it cools the truck down fairly quickly but now I have something else to try.

 

So far since starting this thread and reading what you just posted, it seems to mostly run as it should. I just seem to remember it ran a bit cooler prior to the trans swap. On the much warmer days (90+) and running down the highway at 70+mph, it will inch up to mid 160's to lower 170's. Same with regular stop and go (mild traffic with stoplights and occasional stop signs). I had one time in extreme traffic where it reached just over 190⁰ but slowly came back down after getting moving again and that was also with ambient temperatures above 90⁰. On regular back roads around here staying below 65mph, it seems to settle in around the mid 150's. 

 

So I've kind of come to the conclusion after yours and several other posters here that it's probably working as it should. I think I would have felt more comfortable if the dealer had replaced the TBV which I'm pretty sure they didn't. At least though, I had done the upgraded one myself a few years back. 

 

I do have a trip planned next week where I am planning on camping for a few days. Pulling my toy hauler should give me some idea on how it's working. That's kind of my biggest concern and will give me a good idea on where I stand. I will update this thread after that with what I found. 

[newdude]

On 5/19/2024 at 1:48 PM, mikeyk101 said:

Now I've started down the rabbit hole and wonder if I got the correct replacement transmission. There are 3 possible choices. 

 

1. 19431764

Description:
Sierra, silverado. 4wd. 5.3l. Exc.Heavy Duty Towing Package. Tahoe. 6 speed trans. All. Without towing package. Yukon. 5.3l. 6 speed trans. Suburban. 5.3l. 4wd. Yukon XL. 6.2l. Without denali. 4wd. 6 spd trans. Without enhanced towing.

 

2. 19431766

Description:
Heavy Duty Towing Package. Sierra, silverado. 4wd. 5.3l. Suburban. 5.3l. 4wd. With towing package. All. Tahoe. 6 speed trans. 4wd. Yukon. 5.3l. 6 speed trans. 4wd. Yukon XL. 6.2l. Without denali. 4wd. 6 spd trans. With enhanced towing.

 

3. 24279588

Description:

Sierra, silverado. 4wd. 5.3l. With enhanced towing pkg. Escalade ESV. 8 spd trans. Sierra, silverado. 4wd. 6.2l. Yukon XL. 6.2l. Exc.code-6u3l,6u8l. Yukon. 6.2l. 6 speed trans. With denali. 4wd.

 

 

On mine, I don't have heavy duty towing but I do have the Z82 "Trailering Package" which includes the auto locking rear differential. I also have the 3.42 gears. I am confused between Trailering Package and Towing Package. I know I don't have a Heavy Duty Tow Package but would I have what could be considered enhanced towing package? The reason I ask is because the reman trans that got installed specifically says "Exc.Heavy Duty Towing Package" as well as "Without towing package". I would have thought the Z82 Trailering might be considered the enhanced towing????

 

Now I'm concerned that I may have issues when towing my toy hauler camper. It comes in around 6200lbs loaded...

 

 

19431764 would be correct for your truck.  That covers 5.3s without NHT max trailer.  

 

19431766 is with NHT max trailer.  

 

24279588 is an 8 speed.  

[newdude]

18 hours ago, UsualSuspect said:

I picked up a 2019 LD with 16k on the clock, thankfully still under the 5/100k power train warranty. I complained about surging and high temps 200+. The dealer said they couldn't duplicate it, wouldn't change it unless I wanted to pay for it, and they fought for me trying to get it approved, but the area rep said no. GM trying a save $60 in parts, and maybe $100-$200 in labor last week, is now costing them a transmission. The area Rep had to approve the replacement, now the wait for the tranny, I am not sure if it will be a reman or a new one. Either way, that was one expensive TBV for GM.

 

 

It will be a GM reman.  They don't make new ones anymore.

 

 

On 5/19/2024 at 1:17 PM, mikeyk101 said:

Drive home...  Started off in city traffic after truck cooled off for hour and a half. 9 miles of city driving. Outside temperature is right around 75⁰. Trans temp got to upper 170's. Then 26 miles of highway driving at between 75-80 and temp dropped but bounced between lower and mid 160's. Finally 25 miles of 2 lane back roads with occasional stop sign, traffic signal and roundabouts. Speeds of around 55-60mph. Temp ran mostly mid 160's but never dropped below 162 and got as high as 177 at one point.

 

I know on the positive that these temps are still below the old normal of mid 190 but still higher than I feel they should be. And especially after doing the pill flip mod, they are much higher than they should be. 

 

Based on last discussion at dealership when I got oil change, I'm pretty sure they will tell me that these are normal but I know they are not. Not sure what to do next. I did check trans fluid level and it's fine. It doesn't smell burnt. 

 

 

Assuming the coolers are clear (nothing blocking them), my only other though here is if you have an earlier built 2016.  Early build, the transmission has the aux cooler but it goes though the radiator first, then to the aux.  Later trucks don't go through the radiator at all.   

 

They can be identified via the radiator.  If you see two smaller diameter lines going into fittings on the left side of the radiator, you have the early design setup.  In which case, TBV or no TBV, you will see higher temps than a late truck.

 

Late trucks use only the "aux" cooler as the ONLY cooler.  My 2019 old body (LD) for example that I had used the late lines.  With the TBV bypass/delete, it would struggle to maintain 100F in the winter, but beating the piss out of it on a hot and humid day it wouldn't go past 145F.  I eventually put the 70C TBV on and year round it would be 145-155F, beating on it would see 165F.  

[newdude]

duplicate.

Edited July 4 by newdude

[Grumpy Bear]

1 hour ago, mikeyk101 said:

 

So far since starting this thread and reading what you just posted, it seems to mostly run as it should. I just seem to remember it ran a bit cooler prior to the trans swap. On the much warmer days (90+) and running down the highway at 70+mph, it will inch up to mid 160's to lower 170's. Same with regular stop and go (mild traffic with stoplights and occasional stop signs). I had one time in extreme traffic where it reached just over 190⁰ but slowly came back down after getting moving again and that was also with ambient temperatures above 90⁰. On regular back roads around here staying below 65mph, it seems to settle in around the mid 150's. 

 

 

Yea, there is something I didn't consider. Speed. Big impact on fluid temperature as will be towing. I never drive that fast sustained. 62 mph/100 kph is my normal sub 80 F speed. 56 mph/90 kph (25 mps) if it's hotter. The sweet spot of max cooling in free air for a fin exchanger. 

 

You just need more cooler. They built these things on the edge of the cliff and a few, fall over. 70C TBV was a step back from the cliff but that didn't increase the cooler capacity. GM needs a When the bypassed the radiator and went straight fin cooler that was a useful and major improvement. 

[mikeyk101]

3 hours ago, newdude said:

19431764 would be correct for your truck.  That covers 5.3s without NHT max trailer.

 

Ok, that's the one they installed.

 

3 hours ago, newdude said:

Assuming the coolers are clear (nothing blocking them), my only other though here is if you have an earlier built 2016.  Early build, the transmission has the aux cooler but it goes though the radiator first, then to the aux.  Later trucks don't go through the radiator at all.   

 

I checked the door jam sticker and it shows a Dec 2015 build. And it has just like you described, one lower fitting on left side of radiator and an upper metal pipe that appears to come out of radiator and snake around to the condenser. So your explanation makes sense and looks like what I have seen is normal. 

 

3 hours ago, Grumpy Bear said:

You just need more cooler. They built these things on the edge of the cliff and a few, fall over. 70C TBV was a step back from the cliff but that didn't increase the cooler capacity.

 

I will keep this in mind. Might be a nice upgrade to do. I think the aftermarket billet torque converter might be more useful. My biggest hesitation though is that the reman trans has a 3 year 100k warranty. And although it would be better for the trans than the stock one, I wonder if the trans failed in that time frame if they would give me a hard time over installing an aftermarket part. Replacement transmissions are not cheap...

[mikeyk101]

4 hours ago, newdude said:

Assuming the coolers are clear (nothing blocking them)

Just curious, do you have a suggestion on a simple way to check for blockage?  Would it be possible to just disconnect the lines at the TBV and maybe use a compressor to blow through one of the fittings? And I assume that I will lose some trans fluid coming out the other hose. Is there a simple way to refill those lines after? Will the fluid just automatically start circulating again?

 

It does seem like everything is working as it should but maybe for my peace of mind, maybe confirming that those lines are free flowing would make me less concerned.

[mikeyk101]

4 hours ago, Grumpy Bear said:

Yea, there is something I didn't consider. Speed. Big impact on fluid temperature as will be towing. I never drive that fast sustained. 62 mph/100 kph is my normal sub 80 F speed. 56 mph/90 kph (25 mps) if it's hotter.

 

I travel the Tri-state up and down twice every weekend for about 45 miles each way or so. Unfortunately if I was driving at those speeds, it would make me a hazard to everyone else. It would do wonders for my gas mileage though...

[Grumpy Bear]

1 hour ago, mikeyk101 said:

 

I travel the Tri-state up and down twice every weekend for about 45 miles each way or so. Unfortunately if I was driving at those speeds, it would make me a hazard to everyone else. It would do wonders for my gas mileage though...

 

I know that piece of road. Drive it myself on occasion. Pretty sure the speed limit there isn't 75 mph BUT I also know no one on the stretch drives the speed limit.  More cooler then. 

 

I've used this analogy several times, but it fits here. Suppose GM said they would only warranty your truck if you parked outside, and you lived in an area where softball hail was common. Would you wait until the warranty was over before you took shelter? 

 

Then there is this. The warranty is on the Transmisson, Not the converter, right? If one has an impact on the other, then Weathertech floor mats are warranty killers. 

[newdude]

3 hours ago, mikeyk101 said:

Just curious, do you have a suggestion on a simple way to check for blockage?  Would it be possible to just disconnect the lines at the TBV and maybe use a compressor to blow through one of the fittings? And I assume that I will lose some trans fluid coming out the other hose. Is there a simple way to refill those lines after? Will the fluid just automatically start circulating again?

 

It does seem like everything is working as it should but maybe for my peace of mind, maybe confirming that those lines are free flowing would make me less concerned.

 

 

GM used to actually have a cooler flush and flow machine that was used to power flush the lines and coolers and check their flow rate.  That machine at 99% of dealers has now been delegated solely to 8 speed shudder fixes LOL.  It only gets Mobil 1 LV ATF HP ran through it.

 

As far as DIY, you could probably use air, there is also pressurized cleaners like in this video:

 

 

 

 

Edited July 5 by newdude

[mikeyk101]

2 hours ago, newdude said:

As far as DIY, you could probably use air, there is also pressurized cleaners like in this video:

 

Ok, I think that will be simple enough. On mine, I would probably still use one of the lines coming out of the TBV and figure out a way to capture as it comes out the other. And when finished and lines reconnected to TBV, (mine for now has the pill flipped) will they just fill up and circulate again, and I just top off trans fluid at dipstick tube after letting it warm up?

[mikeyk101]

4 hours ago, Grumpy Bear said:

Then there is this. The warranty is on the Transmisson, Not the converter, right? If one has an impact on the other, then Weathertech floor mats are warranty killers. 

 

Very valid points and worth considering. One thing I almost ran into when trans failed, service writer got me concerned because he said that any kind of lift kit or oversized tires and GMPP would probably deny the repair. He said it happened to several of his other customers recently. I have a 2" level on front with the Rancho Quicklifts and have 275/60R20 instead of the 275/55R20 stock size. But both of these are rather mild upgrades compared to 6" or bigger lift kits or 35" tires. Luckily the guy on other end of phone call to GMPP related that the dealer only had to drop the pan and if there were metal shavings in pan, I would be fine and would be approved. I was happy to hear that part.

 

4 hours ago, Grumpy Bear said:

know that piece of road. Drive it myself on occasion. Pretty sure the speed limit there isn't 75 mph BUT I also know no one on the stretch drives the speed limit.  More cooler then. 

 

Maybe not 75 but from Wisconsin border almost all the way to Chicago, it is 70mph for most of it. Going back up, for some reason, the speed limit is 65mph until closer to Wisconsin. And you're absolutely correct in that very few follow the speed limit...