High altitude/cold weather hesitation with MT gears 2 & 3

Hello!

I'm a first time Tacoma owner in northern Colorado and am brand-spanking new to the forum. I've got a '22 Tacoma with manual transmission and a little under 5k on the odometer.

Of all the manuals I've owned or driven, I think the Tacoma may be the most challenging to drive well. It took me about 3k miles to break old habits (especially floating out of gear without the clutch for up shifts), figure out what worked, and build the muscle memory to be consistently smooth.

That was all fine and good, and I was feeling pretty pleased with myself until I encountered a new issue... recently, when we had our first round of cooler temps I noticed that what had been working beautifully for 1-2 and 2-3 shifts was causing a strange hesitation or lurching.

It is most pronounced in the 1-2 shift, where I get it into 2nd around 2k rpm, am completely off the clutch, and depress the throttle. It'll go for a second, bog out, and then hop back. It feels a bit like trying to ride a dirt bike with the choke on (or what I think that felt like based on 20 year old memories!).

At first I suspected I got bad gas. I topped off that tank with premium gas from another station and it got better, but that also corresponded to warmer temps... Now it's consistently into the 30s around here and the issue is back.

I searched around a bit and found this thread: https://www.tacomaworld.com/threads/boggin-jumping-during-1st-and-2nd-gear-6speed-mt.678055/

OP seems to be describing the same issue in that thread, but the discussion was inconclusive.

I'm going in for my 5k service in a couple weeks and I'm wondering if this is something they can address.

Is this just an issue with the stock tune? I've tried to look into tuning, but... there's some deep enthusiast lingo that I'm finding difficult to penetrate.

Maybe a combination of winter blend gas and high altitude interacting badly with the stock tuning?

Thoughts welcome!

 

It’s possible your truck has an oddball issue, but I’m putting my bets on you not adjusting your driving habits. If I understand what you mean by lurching, it’s caused my applying too much throttle at too low of rpm. Try shifting at a higher rpm or using less throttle after shifting.

I agree that the 1-2 shift on the 6mt taco is a bit finicky, but I adjusted to it a long time ago.

I’ve not noticed a big difference in the behavior due to temperature. I have noticed that if I leave the truck parked outside for extended periods in sub 0F weather, the clutch is feels like molasses. It can take 1-2s to rise from the floor to the up position. This is Annoying as hell and I’ve never experienced it with any other clutch. Luckily I rarely need to park outside over night.

 

Yes, you're right that I can finesse my way around it with gentler throttle application or by shifting at or above 3k, but it just seems strange that it only does it in low ambient temps. I'm okay with just needing to work around it - I just want to make sure it's not a deeper issue that I should be addressing.

 

I edited my post after you quoted it and added a comment about temperature. Define “low ambient temperature”.

 

From my experience the taco shrugs off the cold (except for the clutch), but I live at 800’ above sea level. The high altitude might be the larger issue.

 

Rev it above 2K when making the 1-2 shift. Unlike the 4.9, this engine likes to be revved a bit.

 

It seems like anything around or below 30 (not very low to a Minnesotan!)

I agree about the molasses clutch too. I'll drop it in an up shift and it creeps for a split second and then slaps the bottom of my foot. Haven't driven it in any truly cold temps yet...

 

Mine does this as well when starting and then is fine as the engine starts to warm up, which it usually is warm enough by the time I reach the end of my street. I definitely would expect the elevation to be a factor as well - I'm only around 750 ft above sea level.

 

Thanks for the feedback. Mine definitely gets better as the engine warms, but it persists even after. I agree, I think the altitude could be playing a big factor - I'm over 5' ft here ...

 

I have to admit that I am old enough to have driven trucks with 90hp, carburetors, analog point and coil ignition, 10w30, and block heaters needed to start them in the morning, so I find modern vehicles to be works of magic.

 

My first vehicle was a '79 Chevy Silverado, and I agree they've come a long way!

My new Tacoma is black, just like that Silverado - I feel like I've come full circle.

 

I spend winters up in Tahoe (6,200’ elev)
And mountain cold. The taco is not phased by the cold…
I’ve felt no hesitation as you describe.
Have the dealer take a look…

 

Thanks - do you know about what rpm you generally make the 1-2 shift at?

 

This manual/clutch system is taking me a bit to get used to also. I'm at 1800 miles and as much as I hate to admit it I am finally getting really smooth with it. I had several trucks with manuals back in the day and just sold a 2013 manual ford focus when I got my Tacoma and this beast definitely has it's own way of doing things.

It's fine doing things that would bog down another vehicle, and then it want's to fall on it's face when I think it ought to have no problem! Learning is part of the fun I guess, and this really is a fun truck to drive.

 

Just get an aftermarket ecu tune.

 

I think you’ve got to shift at higher rpms. Once the truck warms to operating temp it goes easier. But at cold startup you should run 1st out to 3-4K and the shifts will get smoother. I hate doing it, but it seems to work. I’m used to low end power, so the taco was quite a transition. I can only imagine that elevation is just making this more pronounced, but I’m at like, well sea level. Maybe 60’ above at the high points. With the occasional climb to 1000’.

 

Definitely need to shift higher. I always shift from 1-2 at no less than 4000 rpm but usually more like 4500 which equates to around 20-25 mph. 2nd gear is just too tall to be used smoothly at much less speed/rpm than that. 2nd gear is half the gearing of 1st, so if you shift at 4,000 you’ll be at 2,000 after. That’s about where you want to be to be able to easily pick up speed in 2nd so it doesn’t do the lugging throttle bounce thing.

Obviously you’ll end up in 2nd gear at inopportune times occasionally, no way around it. My least favorite of those times is rolling up to a stop light, slowing down to about 5-10 mph and then it turns green. Too slow to want to use 2nd, too fast for me to enjoy rev matching into 1st smoothly. I usually just do 2nd and lug my way through. That is one of my least favorite things about this truck. 2nd gear should be 2.5:1, not 2.0:1. A regear will help that for me significantly.

It really doesn’t help that the truck has practically no torque at all at idle. This is by far the lowest low end power I’ve ever experienced in a truck/SUV. The high end performance is decent.

 

That engine needs 4600 rpm to generate max torque. Older vehicles would get their torque at 2000-3000 rpm. Sounds like you're upshifting too early.

 

I live in Summit County, and have encountered similar issues last winter with my then new to me 17 OR DCSB. A good tune will help, as well as getting used to shifting at higher RPMs, but I also suspect that some of the issue is from the damned clutch accumulator not liking the cold, either. I have the parts, but have yet to ditch it, so I can't confirm that theory, but I do strongly suspect it.

 

Of course it depends…
It depends on how much power will be required upon landing onto second gear.
(E.g. uphill vs. downhill).

do try shifting at a bit higher rpm if you find it lugging.

experiment a bit. You’ll get there. It is a bit of an odd combination and the truck is heavy.

the MT makes it fun to drive ‘slow’.

overall, it is a capable combo once you accept it is not a Miata or GTI!