Towing in 4th gear, automatic

2014, V6, automatic, towing package, smallish 2 axle trailer (max gross 4500 lbs), seldom over 2500-3000 payload, making several trips from CA to KS over the couple of years--just completed one, and depending on route, some hills and mountains, so we do most running in 4th, unless on an extended flat.
Question: does anyone know of any potential problems from running in 4th so much? Toyota doesn't seem to want to comment much on this. Many thanks.

 

4th gear in the a750 series transmission is direct drive or 1:1 and is the gear you are suppose to tow in . I wouldnt tow in overdrive or 5th gear mind you

Towing bible http://www.tacomaworld.com/forum/towing/4031-tacoma-towing-bible.html

 

I have the first gen with a v6 and I moved from az to pa a month ago and I was towing a uhaul trailer that was a 14 footer . The trailer alone weighs 2000 ponds and I had 1200 ponds in it so 3200 pounds traveling 2500 miles . I turned off the overdrive when going up hills or going down hills and had no problem . I was doing about 60 all the way through at cruising speed on fat roads . Hope this helps .

 

Toyota won't comment on this, and they ended up buying a new tranny for my 02 Tundra. With pretty much any truck, it is not recommended to tow in any overdrive gear as the gears are not strong enough to deal with towing for any length of time. In my Tundra it means towing in 3rd (OD button in off position). In a Tacoma it means towing in 4th (5th is the OD gear, 4th is 1:1). I've done several trips to Moab from Ca. towing an FJ40 on a flatbed trailer (about 6,000#). The first trip I used OD and ended up eating the OD gear in the tranny...since then I have towed only in high gear (not OD) and actually get better overall mileage than I did the one trip I used OD. Before I ever towed I had asked Toyota Tec and was told "it's fine to tow in OD, just kick it off if you are in the hills".....after I blew a tranny I had a talk with Marlin of Marlin Crawler fame who has a Tundra with 250+k and tows all the time...his advice, DON"T EVER TOW IN OVERDRIVE" regardless of the make of the vehicle unless you want to buy trannies.

 

Many thanks to all--really useful to hear experience.

 

90k miles on my 2009 DCSB Sport with towing package and supercharger. I tow my 5,400lb trailer at 70mph in OD all the time. I only use 4th when it's hunting between gears. Zero issues, and I am NOT easy on the truck. Search it, there's good info out there why it's fine. Trannys usually blow due to heat......

 

Are you running the stock transmission cooler (part of the factory tow package) or have you gone to a larger transmission cooler?

 

Stock everything except the supercharger. I've pulled through the mountains from Bristol, Tn., to Danville, Va. twice in 90 deg summer heat with no issues.

 

^ I wouldn't tow anything over 2k lbs in OD. Leave it in '4' on the AT.

 

Assume overheating is the cause of the transmission damage? I tow a small motorcycle trailer. If the transmission temperatures stays below 220 (per the scan gauge II), I should be ok running in OD, right? Why make it run a higher RPM if the tranny temp is staying in an acceptable range?

 

RockLobster –

I’m feeling a fair amount of gear hunting and converter locking/unlocking, but I assume it’s within an acceptable amount.

Bottom line is if I'm watching my transmission temperature on the scan gauge and it stays under…let’s say...225ish, then I can assume that the amount of gear hunting and converter locking/unlocking I’m experiencing is not damaging the transmission, right???

 

The issue is lockup. When you tow the first thing that happens the lockup disengages then the converter begins to slip then the trans temp goes up. If it's shifting up and down even the lockup disable it.