1. Welcome to Tundras.com!

    You are currently viewing as a guest! To get full-access, you need to register for a FREE account.

    As a registered member, you’ll be able to:
    • Participate in all Tundra discussion topics
    • Transfer over your build thread from a different forum to this one
    • Communicate privately with other Tundra owners from around the world
    • Post your own photos in our Members Gallery
    • Access all special features of the site

Towing trans tests

Discussion in '2.5 Gen Tundras (2014-2021)' started by Creepbam, Jan 5, 2022.

  1. Jan 5, 2022 at 8:28 AM
    #1
    Creepbam

    Creepbam [OP] New Member

    Joined:
    Jul 31, 2021
    Member:
    #66191
    Messages:
    17
    I have a 2020 CrewMax 4x4. Currently running 5w30 oil.Reading all the threads related to trans temperatures on the non cooler models, I thought I'd try some stuff

    Outside temperature was 88-92 F towing around 3000lbs of side by side. The tow was 10.5 hours around 70 mph on slightly hilly Texas country. Slight headwind.

    I drove with tow haul in S4 per owners manual. Trans and oil temp never exceeded 218 degrees. RPMs were around 3k. During this trip when I would get to a flat stretch I'd push it up to s5. Trans temp and oil temp would almost instantly go to 225-230 and hover around there.
    On the return trip post cold front. 35F temps resulted in 205 Trans temp

    Some things I've read on this forum the 218 temp isn't too far off from what some user are getting towing with factory cooler.

    Just throwing this out there for some data for you guys. Keep her and s4 when towing and those insane Trans temps you hear about don't seem to happen.
     
    panicman, LS3, Cpl_Punishment and 2 others like this.
  2. Jan 5, 2022 at 9:04 AM
    #2
    Johnsonman

    Johnsonman New Member

    Joined:
    Nov 25, 2019
    Member:
    #39132
    Messages:
    1,205
    Gender:
    Male
    Austin
    Vehicle:
    Sequoia
    LED headlamps/fogs; interior footlamps.
    I hate the idea of 3K rpms for extended periods, but oh well....
     
  3. Jan 5, 2022 at 9:12 AM
    #3
    Clemsonman14

    Clemsonman14 New Member

    Joined:
    Aug 9, 2020
    Member:
    #50545
    Messages:
    303
    Vehicle:
    2020 SR5 Crewmax 4x2
    302 I believe
     
    2mchfun and ColoradoTJ like this.
  4. Jan 5, 2022 at 9:12 AM
    #4
    Unclebuck

    Unclebuck New Member

    Joined:
    Jun 8, 2021
    Member:
    #64032
    Messages:
    88
    Vehicle:
    2018 Crewmax SR5 TRD Offroad
    Is that for fuel consumption? Running in mid 3k is nothing on this engine and tranny.
     
    Y0TA PR0 and AZBoatHauler like this.
  5. Jan 5, 2022 at 9:13 AM
    #5
    Asimov2025

    Asimov2025 Not Sure

    Joined:
    Feb 19, 2020
    Member:
    #42850
    Messages:
    1,009
    Gender:
    Male
    North Texas
    Non-stop mods
    The owners manual does not tell you to tow in S4...there is one specific situation they suggest towing in S4.
     
    sask3m and ColoradoTJ like this.
  6. Jan 5, 2022 at 10:02 AM
    #6
    Oey12

    Oey12 New Member

    Joined:
    Apr 15, 2020
    Member:
    #45061
    Messages:
    1,492
    Gender:
    Male
    First Name:
    Joey
    New York
    Vehicle:
    2020 SR5 TRD OFFROAD
    Coach Builder 1 inch lift strut spacers Coach Builder 1 inch shackles TRD Sway Bar Diode Dynamics SS
    While technically speaking this is true but the manual does say not to tow in “D”. I have been dropping a gear with towing and/or while carrying heavy loads since I owned my 89’ 4Runner. Seven Toyota trucks later never had a blown engine or transmission (knock on wood) due to it. The 4Runner needed a head gasket as 475k though…. If done properly it will simply not damage a thing.

    And @Johnsonman you have nothing to worry about the engine running a 3k except how your going to pay for the extra gas ;)
     
    tundratoofun likes this.
  7. Jan 5, 2022 at 10:06 AM
    #7
    hagrid

    hagrid The most diverse of Diversity Hires!

    Joined:
    Dec 5, 2018
    Member:
    #22645
    Messages:
    1,976
    Gender:
    Male
    First Name:
    Spraynard
    Pittsburgh
    Vehicle:
    K1600GTL ZX-14R
    paynuss stretchers
    Do yinz mean to tell me I could've kept my '19 PRO by staying in S4 instead of selling it before the transmission exploded in a conflagration that would vaporize everything within 300 yards?

    f*ck my life.
     
    Piki, Ericsopa, bflooks and 2 others like this.
  8. Jan 5, 2022 at 10:18 AM
    #8
    Asimov2025

    Asimov2025 Not Sure

    Joined:
    Feb 19, 2020
    Member:
    #42850
    Messages:
    1,009
    Gender:
    Male
    North Texas
    Non-stop mods
    Gosh I must have missed that. I thought I had read everything on towing. Do you have a screenshot where they tell us to not tow in Drive?

    PG187.jpg

    PG173.jpg
     
    AZBoatHauler likes this.
  9. Jan 5, 2022 at 10:27 AM
    #9
    303Tundra

    303Tundra New Member

    Joined:
    Dec 31, 2021
    Member:
    #72494
    Messages:
    27
    Denver
    Vehicle:
    2021 Tundra Platinum
    I have a 2021, so I was curious about this and read through the manual. The spot where it mentions 4s is a bullet point about engine braking efficiency.


    "To maintain engine braking efficiency and charging system performance when using engine braking, do not use the transmission in D. Transmission shift range position must be in 4 in the S mode."


    I'm thinking that means they're recommending to use 4s when wanting to engine brake. Very well could be understanding it wrong though.
     
    ColoradoTJ likes this.
  10. Jan 5, 2022 at 10:28 AM
    #10
    Oey12

    Oey12 New Member

    Joined:
    Apr 15, 2020
    Member:
    #45061
    Messages:
    1,492
    Gender:
    Male
    First Name:
    Joey
    New York
    Vehicle:
    2020 SR5 TRD OFFROAD
    Coach Builder 1 inch lift strut spacers Coach Builder 1 inch shackles TRD Sway Bar Diode Dynamics SS
    No I do not, however why is the exact statement that you posted from the manual (and the same exact statement I was implying) is under the towing section? The reverse here is where does Toyota state you can’t tow in 4S? If it were in a different section I would tend to agree but it’s specifically under towing hence why I said technically…
     
    AZBoatHauler likes this.
  11. Jan 5, 2022 at 10:36 AM
    #11
    Asimov2025

    Asimov2025 Not Sure

    Joined:
    Feb 19, 2020
    Member:
    #42850
    Messages:
    1,009
    Gender:
    Male
    North Texas
    Non-stop mods
    That statement I posted is specifically for if you are using "Engine Braking" and does not apply any other time.
     
    ColoradoTJ and 303Tundra like this.
  12. Jan 5, 2022 at 10:39 AM
    #12
    Cpl_Punishment

    Cpl_Punishment Young men never die.

    Joined:
    Jan 24, 2019
    Member:
    #25048
    Messages:
    14,229
    Gender:
    Male
    First Name:
    Rosy
    Alberta, Canada
    Vehicle:
    2020 MGM SR5 CM 4X4
    Boost Auto mirrors, RSB, Leer Legend canopy, Line-X bed liner
    Sure, but if everyone sees lower temps in S4, why not use it? As @Oey12 says, it doesn't say not to tow in S4.
     
    Unclebuck and Oey12 like this.
  13. Jan 5, 2022 at 10:41 AM
    #13
    303Tundra

    303Tundra New Member

    Joined:
    Dec 31, 2021
    Member:
    #72494
    Messages:
    27
    Denver
    Vehicle:
    2021 Tundra Platinum
  14. Jan 5, 2022 at 10:41 AM
    #14
    Oey12

    Oey12 New Member

    Joined:
    Apr 15, 2020
    Member:
    #45061
    Messages:
    1,492
    Gender:
    Male
    First Name:
    Joey
    New York
    Vehicle:
    2020 SR5 TRD OFFROAD
    Coach Builder 1 inch lift strut spacers Coach Builder 1 inch shackles TRD Sway Bar Diode Dynamics SS
    I completely understand that, but again it’s under the towing section. Which would suggest to a owner to use engine breaking during towing, meaning it’s safe in my interpretation. Even though it’s intended cause is not to lower transmission temps
     
    Cpl_Punishment likes this.
  15. Jan 5, 2022 at 10:43 AM
    #15
    Asimov2025

    Asimov2025 Not Sure

    Joined:
    Feb 19, 2020
    Member:
    #42850
    Messages:
    1,009
    Gender:
    Male
    North Texas
    Non-stop mods
    Can't help ya. Carry on.
     
  16. Jan 5, 2022 at 10:45 AM
    #16
    JDR76

    JDR76 New Member

    Joined:
    Jun 22, 2021
    Member:
    #64642
    Messages:
    510
    Gender:
    Male
    WA
    Vehicle:
    2021 1794 TRD OFF ROAD
    That section just states that, while towing and while using engine braking, don't use D. Nothing more or less than that.

    Elsewhere in the towing section, it states "Before towing depress TOW/HAUL button." No where in the "Before towing" section does it state which transmission setting to use (or not use). It leaves that open.

    But I do agree it's not a well written section. This is why I contacted Toyota and asked the question. The e-mailed response that I received stated that you use T/H in D while towing unless using engine braking, in which case you use S4. However, for my personal needs while towing, I generally use S4 and S5, depending on the hills and such.

    Toyota is a bit of a mess though on this. If someone else contacts Toyota and asks the same question, it would not surprise me if they would receive a different answer.
     
    Last edited: Apr 22, 2022
    Oey12 likes this.
  17. Jan 5, 2022 at 10:47 AM
    #17
    AZBoatHauler

    AZBoatHauler SSEM#140/ASCM#3/2ndGenNaysayer/BAF140

    Joined:
    Aug 13, 2019
    Member:
    #34576
    Messages:
    6,935
    Gender:
    Male
    First Name:
    Adam
    So.Arizona
    Vehicle:
    2017 CrewMax 4x4, 2017 LandCruiser, 2005 Sequoia 4x4
    Demello / SOB Fab Bumpers, SuperWinch, WKOR sliders, RCI skids, Baja Designs lighting, Billy 6112 and 5160 w/ CB +2, JL Audio with Alpine HU, DD 10" Exhaust, LED headlights, Rago fab mounts, 35” BFG, HAM radio
    I’ve been driving mine this way since new towing 6,500lbs up 8% grades and it runs like new 5 years and 65k later. 3k RPM isn’t screaming and it gives you way more power than 2k RPMs. Lugging an engine seems far worse than letting it run.
    My boat turns 4.2k rpm on slalom runs. :anonymous:
     
    2mchfun, Cpl_Punishment and Oey12 like this.
  18. Jan 5, 2022 at 10:52 AM
    #18
    68rs75z28

    68rs75z28 New Member

    Joined:
    Sep 8, 2021
    Member:
    #67798
    Messages:
    240
    Vehicle:
    2020 tundra sr5 dc
    Yet we have people reporting that EMPTY.

    My truck reported 215 degrees with an EMPTY load on a 100 degree day.

    With a cooler? Never over 195 EVER even loaded.
     
    2mchfun and sask3m like this.
  19. Jan 5, 2022 at 11:18 AM
    #19
    ColoradoTJ

    ColoradoTJ Certified tow LEO Staff Member

    Joined:
    Feb 24, 2016
    Member:
    #2766
    Messages:
    35,621
    Gender:
    Male
    Colorado
    Vehicle:
    LML 3500HD
    Calibrated Power 5 Tune pack, Allison 1000 tune, PPE deep trans pan, Cold/Hot CAC pipes, Banks CAI, PCV reroute, resonator delete, S&B 62 gal fuel tank, B&W GN hitch
    S4 is a 1 to 1 ratio in the Tundra with converter lock up. This will give you the lowest transmission temps (as people are seeing on here). Fuel economy suffers a bit for sure. For a 2019-2021 Tundra truck with the puck heat exchanger it might be a better way to tow when around 6-8k lbs.

    I did a couple short videos on how if a truck can stay in converter lock up, trans temps really don’t change much.

    Towing 9k lbs in 78* heat, mountain terrain. In 5th gear, converter lockup.



    Almost at destination at 85* ambient temps. So not a fair comparison since the Allison can lockup in 2nd gear, but I tried to keep it in 3rd gear. This dirt road is rough and steep. In the short distance trans temps went up from 140* to 162*.

     
  20. Jan 5, 2022 at 11:28 AM
    #20
    Creepbam

    Creepbam [OP] New Member

    Joined:
    Jul 31, 2021
    Member:
    #66191
    Messages:
    17
    I didn't mean to start a pissing match on to tow in s4 or not. Just stating what I found by towing that way. I also had a "absolute engine load" Guage on OBDFusion and while in S4 it was significantly lower than when S5 was used.
     
  21. Jan 5, 2022 at 12:14 PM
    #21
    ColoradoTJ

    ColoradoTJ Certified tow LEO Staff Member

    Joined:
    Feb 24, 2016
    Member:
    #2766
    Messages:
    35,621
    Gender:
    Male
    Colorado
    Vehicle:
    LML 3500HD
    Calibrated Power 5 Tune pack, Allison 1000 tune, PPE deep trans pan, Cold/Hot CAC pipes, Banks CAI, PCV reroute, resonator delete, S&B 62 gal fuel tank, B&W GN hitch
    It really isn’t a pissing match. If I owned another Tundra in the 2018 or older model, I would tow in D/TH mode and shift to S4 and lower for steep grades for engine braking. I rarely towed under 7500 lbs with my 2nd Gen and I was in 3rd and 4th gear most time anyway with the motor singing away at 2800-3800 rpm all day long.

    Now if I owned a 2019-21 Tundra and towed 7k or more, my first upgrade would be the factory upgrade back to 2018 and prior years. When a Toyota Engineer totally recommended doing this mod, all I need to know.
     
    AZBoatHauler likes this.
  22. Jan 5, 2022 at 3:57 PM
    #22
    batman900

    batman900 Yep

    Joined:
    Jun 28, 2020
    Member:
    #48593
    Messages:
    655
    Vehicle:
    24-RAM 2500, 05-Tundra, 11-Accord
    Indeed S4 helps a lot so long as you don't mind going a bit slower. I used it and took the smaller highway at 65mph as opposed to HWY-35 at 75mph "people go 80-85mph." I would top out around 223F with 3-4k pounds. S4 is a good band aid if you don't need the full aftermarket upgrade which I highly recommend.
     
  23. Jan 5, 2022 at 5:42 PM
    #23
    Cpl_Punishment

    Cpl_Punishment Young men never die.

    Joined:
    Jan 24, 2019
    Member:
    #25048
    Messages:
    14,229
    Gender:
    Male
    First Name:
    Rosy
    Alberta, Canada
    Vehicle:
    2020 MGM SR5 CM 4X4
    Boost Auto mirrors, RSB, Leer Legend canopy, Line-X bed liner
    Is now a good time to point out that the manual says not to exceed 65 when towing?
     
    Oey12, GODZILLA, JDR76 and 2 others like this.
  24. Jan 6, 2022 at 4:03 AM
    #24
    batman900

    batman900 Yep

    Joined:
    Jun 28, 2020
    Member:
    #48593
    Messages:
    655
    Vehicle:
    24-RAM 2500, 05-Tundra, 11-Accord
    I know it, I just can't be that guy going 20+ less than everyone else so long as my load/trailer is safely controlled. I'm not trying to win a race but I at least want to keep up. I'm sure recommendations like that are included for liability reasons. Nobody wants to be responsible for Joe Brown and his 5th wheel horse trailer getting out of control when he's twice over the limit of his half ton.
     
  25. Jan 6, 2022 at 4:06 AM
    #25
    nobodyintexas

    nobodyintexas What?

    Joined:
    Jun 22, 2020
    Member:
    #48303
    Messages:
    3,881
    South of Houston
    Vehicle:
    S/C'd 2020 White 1794 Tundra
    Whatever this forum told me to do
    I resemble this remark.
     
  26. Jan 6, 2022 at 4:44 AM
    #26
    glowblue

    glowblue From time to time

    Joined:
    Mar 28, 2019
    Member:
    #28267
    Messages:
    1,941
    Gender:
    Male
    First Name:
    Brian
    VA
    Vehicle:
    2021 Tundra SR5 —> 2021 F-250 XLT
    You didn’t start a pissing contest, it’s been raging for a while on this forum. @hagrid is the resident transmission temperature guru and can provide counseling and therapy for those transmission temperature blues!
     
    GODZILLA, ColoradoTJ, hagrid and 2 others like this.
  27. Jan 6, 2022 at 4:46 AM
    #27
    nobodyintexas

    nobodyintexas What?

    Joined:
    Jun 22, 2020
    Member:
    #48303
    Messages:
    3,881
    South of Houston
    Vehicle:
    S/C'd 2020 White 1794 Tundra
    Whatever this forum told me to do
    I come here for the @hagrid wisdom.

    it is the comic relief to the Tundra epic.
     
    Ericsopa, GODZILLA, hagrid and 2 others like this.
  28. Jan 6, 2022 at 6:32 AM
    #28
    blanchard7684

    blanchard7684 New Member

    Joined:
    Nov 18, 2018
    Member:
    #21856
    Messages:
    879
    Gender:
    Male
    S4 is indeed a good mitigation for high trans temps while towing. With 4.30 gears and the shift changes, the lock up is maxed and this is why the temps drop. Combined with 3k engine rpm and highway airflow the engine coolant is circulating and removing more heat as well.
     
    JDR76 and hagrid like this.
  29. Jan 6, 2022 at 9:41 AM
    #29
    hagrid

    hagrid The most diverse of Diversity Hires!

    Joined:
    Dec 5, 2018
    Member:
    #22645
    Messages:
    1,976
    Gender:
    Male
    First Name:
    Spraynard
    Pittsburgh
    Vehicle:
    K1600GTL ZX-14R
    paynuss stretchers
    When are people gonna wise up and start using liquid helium to pull heat out of the converter?
     
  30. Jan 6, 2022 at 6:36 PM
    #30
    glowblue

    glowblue From time to time

    Joined:
    Mar 28, 2019
    Member:
    #28267
    Messages:
    1,941
    Gender:
    Male
    First Name:
    Brian
    VA
    Vehicle:
    2021 Tundra SR5 —> 2021 F-250 XLT
    My transparent aluminum idea is better, I just submitted a patent application for it.
     

Products Discussed in

To Top