Re-Gear for towing

Reaching out for some advice. Wondering if it would be worth the cost ($2000ish after core charge refund with ECGS) to regear my 21 DCLB OR with 5.29’s to improve my towing experience. I’m in NW Oregon and the gear hunting on the hills without load drives me crazy. Add 3800lb camper and good luck getting out of 4th Gear. Thankfully I have the Long Range America 33gal gas tank so I don’t have to fill up as much. I’d say average of 8mpg towing and 15mpg without. thanks

 

If you hypothetically regear your truck so that your current 6th is the same gear ratio as your current 4th, what have you gained? The primary difference I see is that a 4 becomes a 6.

 

I've driven tuned models and they hunt a lot less, its actually noticeable.

I'd do a tune long before a gear reduction, the truck transmission will still hunt, you'll just have more torque and less fuel economy.

 

Thanks for the feedback. I do have a tune but doesn’t seem to change much. Then again it’s been about 3yrs since the tune so I can’t remember what it was like before. . I’ve been trying to talk myself out of trading in for a 2nd gen tundra.

 

Just keep it in a lower gear so it doesn't hunt; you shouldn't be towing in OD at any rate.. You stick 5.29 gears in it and you'll hate driving the truck inside 6 months. It kills your low rpm cruising speed, not to mention gas mileage when you're not towing. Don't expect to get any better gas mileage while towing with a lower (numerically higher) gearing.

I drive my 5-speed automatic like a straight drive when I tow and I'm pulling 6000-6500 pound loads sometimes. (2011 4L) I get around 6-10mpg when towing and as much as 21 not towing on the interstate at 65-70.

My FJ40 had 4.10 gears and 60mph had the engine (4.3L straight 6) screaming at 60mph. It got old real fast.

 

If you're dragging that kind of weight around on a regular basis...the Tacoma isn't the right truck for that. Tacomas are OK for occasional towing and normal minimal truck stuff, but towing over 3000lbs or so, find yourself a full sized rig if you're gonna be doing it more than once or twice a year. It's gonna be miserable otherwise.

 

To be fair, you’re not supposed to be towing in the OD gears in stock form. 5.29s would put your 5th gear close to where the current stock 4th gear is, but about 100 rpm lower. So really it’s sort of a wash, except you’d have better acceleration in all the gears….but you’d still be stuck in about the same final drive of the new 5th post-regear.

If I had an auto and towed a lot then it would be 4.30 gears and keep it in 4th for me. The rpm isn’t what’s killing fuel mileage, and getting into a taller gear is probably only going to make things worse. In stock form 5th on the auto is way too tall to tow.

 

The auto in the 3rd gen has such tall overdrives that none of that is a concern. The real concern is gearing so deep that 4th becomes too low to comfortably tow in, because that is the best towing cruise gear.

 

Can you reach out to the tuner & get updated? They can change shift points too

 

As others have said you really don't want to be towing in the overdrive gears at all and the Tacoma isn't really ideal for frequent heavy towing.

I towed cars 1200 miles twice in fourth (manual trans) 3400 RPM and let it eat all the way.
Both trips were about 11.5 mpg and no oil consumed.

 

the whole dont tow in overdrive deal doesn't really account for the diff ratio. if the total final drive ratio in 4th stock is the same as 5th regeared than theres really no difference. the automatic trucks are way undergeared stock so i would regear regardless if towing or not. its literally one of the most popular 3rd gen mods.

also to put something in perspective your manual trans truck has the same final 6th gear ratio bone stock as an automatic truck thats been regeared to 5.29s. thats how much deeper the overdrive gears in trans are.

 

The comment “good luck getting out of 4th gear” by the OP was why I mentioned why in stock form one shouldn’t be using OD on the autos for towing, because per the owner’s manual they say not to, so there should be no desire to get out of 4th. Yes, 5.29 lowering the overall gearing by 35% puts you to where you can use 5th relatively fine for towing; it’s a tiny bit taller than stock, assuming you keep stock tires on both setups. However, regeared 4th will be taller than stock 3rd, and regeared 5th will be slightly worse than stock 4th. So it’s not quite perfect. But nicer for acceleration overall.

What I wouldn’t want is 5.29s on 35’s where 4th is too low and 5th too tall. Makes it awkward to find a good tow gear. For 35’s I’d run 4.88 so that 4th was more geared towards towing. Just an example of why it’s worth considering the whole picture. 5.29s are awesome overall but if it puts certain gears in less useful spots, then it could be counter intuitive and a backwards step.

 

The issue with towing in overdrive isn't about the engines ability to pull in those gears, it is about the side load on the gears in the transmission.

As the overdrive is speeding up the output shaft faster than the input shaft you are getting something for "free" if you will -- of course nothing is truly free. The mechanical advantage of that speed up is the issue, the transmission isn't as strong in overdrive as in the 1:1 ratio 4th gear.


Although not for our 6 speed the photos below illustrate the power flow in 4th gear and overdrive.

4th gear, direct drive, 1:1 ratio, see how the power flow is straight thru the main gearset = strong.




Overdrive gear, power flow through 4 gears and the countershaft = side load, the gears are trying to force themselves apart.



Obviously an automatic is built differently than a manual but the issue is the same, the overdrive section isn't as strong as the 1:1 ratio 4th gear section.

 

To be fair, the owners manual for the manual transmissions does suggest towing in 5th, so that should be safe. Although I felt 5th was too tall on a stock truck for towing. 4th all the way for me. Once I regeared then my 5th became like the old 4th, and so that’s what I use now. And that should be safe since the owner’s manual recommends it.

 

This is where I’m at. Even unloaded I'm rarely able to get into 6th gear (downhill at 70mph). I’m leaning towards the re-gear for all around better driving experience but wanted to see if anyone had experience towing after a re-gear.

 

If you were doing it again would you opt for the 5.29s over 4.88?

 

No, because when I’m not towing, it has plenty of go. Plus the speed limit on the freeways where I live are 80mph.

However, if you run bigger tires permanently, like 33”+ then probably

 

I regeared my truck with 4.56’s since I was only planning on running 33’s. It was a big enough rpm change in 4th to keep the gearing acceptable. I recently jumped up to 35’s and haven’t yet towed with it. My truck also has a Magnuson sc with a smaller pulley and software from Yotawerx. The rpm and vehicle speed range I see when pulling our trailer seems to work well with the steep hills and highway speeds we see.

 

Get a G2 5.7 Tundra, spend the 2k on a good tune, BAMuffler, and do the SABM. You 100% will not regret it!

 

It’s tempting. Worried I will miss the ability to get into the skinnier trails when I’m not towing. Can’t have it all I giess