Need more power for towing

[WCVanHorne]

4S locks out overdrive. 5S will allow the converter to lock/unlock + allow the trans to engage/disengage overdrive. Believe me I tried 5S and you can move along with the converter locked. But overdrive engaged while towing ain't happening.

I know gearing down to 4th (4S) locks out 5th (Overdrive). However my question (and I think the answer is no) is if there is a way to prevent the torque converter from locking but not gear down to 4th. IMHO 5S should do exactly this, but it does not (ECM mod?). Current 5S is really no different than Drive as far as I can tell.

 

[Biggcrisp]

I know gearing down to 4th (4S) locks out 5th (Overdrive). However my question (and I think the answer is no) is if there is a way to prevent the torque converter from locking but not gear down to 4th. IMHO 5S should do exactly this, but it does not (ECM mod?). Current 5S is really no different than Drive as far as I can tell.

You, my friend, are correct. 5S is almost exactly the same as Drive.

Our 5 speed transmission has gears 1-5 plus an additional overdrive gear. 4S is the only way to lock-out that overdrive gear that 5S allows. Yes 5S works the same as Drive does concerning the overdrive operation.

4S towing at 60 - 65 mph equals around 2,500 RPM. The engine noise level starts to get annoying at higher speeds in 4S. I personally have ran 90 mph towing for a short distance (in 4S). Not many vehicles can boast fuel efficiency numbers, while towing, in the 12-16 MPG range at 65 MPH.

On a side note: I recently purchased a RAM 1500 for towing on long distance cross-country trips (and for other personal reasons).

The 4runner is great for those 360 days of non towing. The 4runner cabin is great for family vacations. The truck will be nice to have on those 5 or 6 days of towing at the expense of burning more fuel. The truck cabin is also lacking that enclosed, climate controlled cargo area the 4runner has.

Plan is to also keep the 4runner at least until after the new CAFE standards kick in.

 

[TexasAg]

Or you could do like I did and get a GX460 with a V8.

 

[WCVanHorne]

You, my friend, are correct. 5S is almost exactly the same as Drive.

Our 5 speed transmission has gears 1-5 plus an additional overdrive gear. 4S is the only way to lock-out that overdrive gear that 5S allows. Yes 5S works the same as Drive does concerning the overdrive operation.

Ummm. I believe you are in error here. The transmission is a 5 speed including overdrive (not plus overdrive, ie. 6 speed), in other words 5th is the overdrive:

Gear Ratios
1st 3.52
2nd 2.042
3rd 1.4
4th 1.0
5th 0.716
Reverse 3.224

Attached is the spec sheet.

You get the impression of the "6th" gear when the lockout engages and the tranny stops slipping. I my experience it's around 200 RPM at 120 km/h.

 

[Jeremy556]

So how do you disable the torque converter lockout on the SR5? Going to 5th still allows it to lockout. I'd like to stay in 5th but not have certain load situations when towing where it is hunting between 5th locked out and not.

You want the torque converter locked. When it is locked, the input and output shafts turn at the same rate and the transmission fluid is no longer acting as a clutch. Unless you are going down a grade, and you can use 5th with the converter locked, and not gain excessive speed from gravity, you should stay <5.

 

[024RunnerSE]

Why are people towing with their vehicles if they know nothing about them? The reason why they put an owners manual in the glove box is to tell you how to properly operate your vehicle. I see towing accidents all the time no matter what the tow vehicle caused by people not understanding how to handle their vehicle. If you're not familiar with how to properly shift your vehicle, don't tow. Anyone who tows knows that gearing is a HUGE factor. You should be shifting manually to help save your transmission and to help save your brakes. You should be downshifting at proper RPMs to help slow the vehicle down and your brakes should be assisting. Lugging your engine at low RPMs when towing causes engine/transmission overheating. Sacrifice a bit of fuel economy and shift it yourself. Tow/haul mode basically keeps the transmission from shifting into overdrive on the vehicles with this feature. ECT Power button on older Toyotas made the transmission more sensitive to shifts to assist with keeping the transmission from hunting for gears but I bet Toyota got rid of it because people never knew how to use it anyway. On a side note, you're supposed to gradually accelerate when towing. Expecting the vehicle to accelerate normally when towing a trailer is absurd.

If I can tow over double the weight of my vehicle safely with only "183hp," I think you can move 2700 pounds pretty quickly with an extra 87 horsepower.

 

[MadeInMaine]

Huh?

I think he meant turn off over drive...

Thank for [MENTION=101228]VoodooTitan[/MENTION] , and yes [MENTION=65614]Antman[/MENTION] , my ipad so lovingly autocorrected for me.

I meant that on the '14 SR5, there is no Sport mode, so how do you switch off overdrive?

 

[Biggcrisp]

Ummm. I believe you are in error here. The transmission is a 5 speed including overdrive (not plus overdrive, ie. 6 speed), in other words 5th is the overdrive:



Attached is the spec sheet.

You get the impression of the "6th" gear when the lockout engages and the tranny stops slipping. I my experience it's around 200 RPM at 120 km/h.

Meh...as a married man I get corrected daily.

Here was my experience:

Towing South on IN I-65 set cruise on 62 mph for downhill foot break. Engage family in conversation. Cresting overpass, forgot about cruise, trans kicks down to 3rd gear, get "that" look from :girl::rtfm: So I start paying a little more attention to throttle control and decide to experiment with 5S (screw the manual).

I'm at 62 mph on flat ground running 2,500 rpm in 4S and shift to 5S. RPM drops to 2,200, let up on throttle, 1,800 RPM. Ease up on throttle again and 1,500 RPM. Meanwhile I'm trying (and failing) to maintain speed.

After several tries and determining 1,800 rpm is maintainable at 65+ mph I set cruise. After a couple more overpass incline/decline situations with unlocking uphill and hitting that 1,500 rpm situation downhill along with more of "that" look. I determine 4S is the winner.

 

[VoodooTitan]

Thank for [MENTION=101228]VoodooTitan[/MENTION] , and yes [MENTION=65614]Antman[/MENTION] , my ipad so lovingly autocorrected for me.

I meant that on the '14 SR5, there is no Sport mode, so how do you switch off overdrive?

It's terrible advice, but you could try a sledgehammer. :wink2: :jk:

Is there an OD button on the shift lever? Usually they'll have that as an option, I know it was on older models. I'm not familiar with the SR5. I have a Trail that I haven't been inside of for 5 months...

 

[philsey]

I meant that on the '14 SR5, there is no Sport mode, so how do you switch off overdrive?

It is astonishing how little you know about your own vehicle...

 

[toyota4life]

Thank for [MENTION=101228]VoodooTitan[/MENTION] , and yes [MENTION=65614]Antman[/MENTION] , my ipad so lovingly autocorrected for me.

I meant that on the '14 SR5, there is no Sport mode, so how do you switch off overdrive?

Push shift lever to the left while in drive

 

[MadeInMaine]

It is astonishing how little you know about your own vehicle...

For never towing anything, and owning it for a total of 8 days... I think Im doing all right.

But thanks for your positive comment and great attitude.

 

[jrob]

I'm told by some mustang guys that a supercharger is the best way to add power for towing.
Because science.

Gearing, common sense, and adjusted driving habits to accommodate a trailer is all just a bunch of internet nonsense. Everyone knows moar power is always the answer.

 

[donuts4]

When jeep and ford are offering nearly 400 horsepower in their competing suv's Toyota has missed the common sense part of this deal. So, are the guys at jeep and ford just a bunch of meat heads for wanting that much power in their mid sized SUVs ? No. At least toyota could have offered a towing package that included gearing and tuning suited for towing 4500lbs. They missed a great opportunity.

 

[Jeremy556]

When jeep and ford are offering nearly 400 horsepower in their competing suv's

They don't have competing SUVs. Sounds like you bought the wrong car.

 

[jrob]

So go buy a jeep or a ford then and quit swinging on Toyota's nuts.
How is it that you dropped over 30k on a vehicle whilst completely oblivious to it's towing capability?
4runners have never been known for power.

That said I can haul 3500 lbs worth of motos around the san juans with my 87 22re with little to no issue so...

 

[1engineer]

When jeep and ford are offering nearly 400 horsepower in their competing suv's Toyota has missed the common sense part of this deal. So, are the guys at jeep and ford just a bunch of meat heads for wanting that much power in their mid sized SUVs ? No. At least toyota could have offered a towing package that included gearing and tuning suited for towing 4500lbs. They missed a great opportunity.

Then go buy the 400 hp by all means. It's tough to use though when it's sitting in the frigging shop because of poor designs. Don't believe me? The deciding factor on quality is residual value, or what it's worth after a few years. Toyota 4Runner? Almost 80%. JGC or Expedition? Less than 60%. I despise it when people want all the bells and whistles and crap the other guys offer but want the reliability and value of a Toyota or Honda. You can have it both ways though. It's called a Land Cruiser. $85K gets you the best of both worlds. Can't afford it? Suck it up and choose but don't ***** when you want everything but aren't willing to pay for it.

 

[VoodooTitan]

When jeep and ford are offering nearly 400 horsepower in their competing suv's Toyota has missed the common sense part of this deal. So, are the guys at jeep and ford just a bunch of meat heads for wanting that much power in their mid sized SUVs ? No. At least toyota could have offered a towing package that included gearing and tuning suited for towing 4500lbs. They missed a great opportunity.

Yea I agree they coulda given it around 315hp or 330 hp, easily... but they didn't. And the problem with those companies is... you guessed it, quality and reliability.

When I was in the market we test drove a jeep (grand Cherokee)... Everything was fine, the interior was nice, the ride was nice, it was a bit small inside for an SUV... hell it was really small. Then, as my wife comes to the stop light and comes to a complete stop, she asks the sales guy why the display is still showing the jeep in a higher gear? He says its normal. Um... okay... NO! So the light goes green and she tries to take off. It's barely moving... almost like trying to take off from 4th gear. well whattayaknow! She had to down shift it, then up shift it.

Later that night I look up reviews. They're terrible. People have complained about the jeep not starting due to the electrical system, the transmission not shifting properly, and the jeep shutting off in the middle of operation. No thanks.

No I can't speak for the Wranglers, but I don't know many people who tow with them. Nor do I know what the rated towing capacity is.

As far as ford goes, not interested in the explorer. Never was a ford guy. So I won't bash on them or say anything negative because I'm not a previous owner.

I think Toyota is doing it right. Just my opinion tho. You must too though since you bought one.

 

[WCVanHorne]

You want the torque converter locked. When it is locked, the input and output shafts turn at the same rate and the transmission fluid is no longer acting as a clutch. Unless you are going down a grade, and you can use 5th with the converter locked, and not gain excessive speed from gravity, you should stay <5.

I am well aware of the function of the torque converter lock however you don't always want it locked near synchronous speeds. Towing/certain grades/winds are a typical situation. While the stator based torque multiplication has largely disappeared near synchronous speeds, certainly not enough to be considered a "6th" gear, the additional slip of the fluid coupling allows the engine RPMs to increase enough to reach a stable power/torque point that does not trigger a further downshift to 4th.

Practically I find there are some conditions when for many minutes, or even a good fraction of an hour, I'm at just that point on the power/torque curve that the Tranny/ECM isn't quite happy with 5th locked and cycles "down" to 5th unlocked and then relocks back "up" again.

Another obvious reason to stay unlocked is speed of shifting. The unlocking and re-locking adds latency to the shifts that is undesirable in anything pretending to be a manual or "sport" mode. As I mentioned 5S should be exactly this, 5th with the converter unlocked, for either a manual decision while towing or quick down shifts. If I really want to lock it I can pop it in Drive where it is 90% of the time anyhow and have it happily lock. Again it seems there is no difference between 5S and Drive and this would appear to be a programming bug.

Some reading.

 

[donuts4]

:der: a little sensitive today..

I have an '05 sr5 v8 runner.. So quit bein so dam sensitive. There's no good reason why they aren't offering a v8 in gen 5 ..

I had a new '13 jeep Srt8 and it ran flawless for the 20k miles I had it. I sold it because it was too nice for DD and didn't have ground clearance for off roading.

Toyota failed to improve the drivetrain along with the rest of the truck.. Period.