Over the last few weeks, I've noticed a slight surging of the truck. I've narrowed it down to highway speeds (50-70 MPH) and when just slightly accelerating. It's about every second, the cars surges a bit. My passengers usually don't notice it unless I bring it to their attention, but driving it is noticeable.

I can usually see the RPM's jump a couple hundred during this too. Before that I thought it might be something with the electric motors.

Anyone else notice this? Next time I bring it into the dealer, I'll ask them, but they'll have to find an interstate to test it on, and it's not that big of a deal as long as it doesn't get worse.

 

Hi T-pole I have not noticed anything like this. Let us know what you find out.

 

are you in v8 or v4? is it running with battery assist? are you feeling the switch between battery assist and ICE?

 

the hybrid's tranny is a 4 speed CVT + electric motor or variable auto tranny. it is not the usual slushbox with limited speeds. I guess that is what you are feeling? specially during rapid acceleration and deceleration? I would think it to be normal. but check with your dealer. the worst thing that can happen is they replacing your tranny for a normal behaviour.

 

I haven't noticed if it's in V8 or V4 under normal driving. I can tell you that I was towing an enclosed trailer (1400 mile round trip) where it would only go in v4 downhill, so this 'surging' was in v8 as that was the majority of my driving.

Also, yeah, I've noticed a bit of differences with this tranny compared to a normal one, but this is different from the first year of owning it for sure. I can also get it to do this with and without cruise control.

I don't think that this is happening during the switch from battery assist to just ICE, but I will try and verify with the hybrid screen on the nav.

This forum and the truck have been great, I don't want anyone to take this as complaining about the truck, I'm hoping to put well over 100,000 miles on it before I get rid of it. Theres a lot of well informed people on this forum, and I just wanted to see if anyone else experienced this as well.

I'll update with any more info I can come up with.

Thanks again!

 

This Transmission is tight and very clean, shifting is almost not noticeable, mine does not surge. However does this happen when the trailer is not installed?

 

I agree, that the transmission shifts very smooth.

This however isn't a shifting issue, and yes, it happens without the trailer attached. It's just much more noticeable with the trailer on, because the truck is accelerating more then under normal driving. I'm usually running about 1000 RPM higher with the trailer, and getting about 10-12 MPG. I only tow when I have to!

This morning, I noticed that it was fine while in v4 mode (about 60 MPH). I get this 'surge' under slight acceleration. The truck switches to v8 for the acceleration, and about every second, theres just a slight surge in power during the acceleration. If I give it more or less gas, then it goes away, but I can get it to do it almost every time. The DIC is indicating that it's staying in v8 during this, and not switching back and forth.

I did forget to check if it was switching between battery assist and ICE only though.

 

That could be the electric motors switching from motor to generator and back.

 

Another possibility would be dirt in an injector, or possibly the breakdown of a spark plug or ignition lead a 200-300 RPM surge on the ICE indicates something. Fuel Filter? Just ideas.

 

All good ideas. I'm thinking it's something in the computers/programming/throttle position sensor, etc.

On my drive home from work, the truck was mostly in v4 mode, and couldn't get it to duplicate the problem once. So, it's something that only happens in v8. Well, that could then be one of your suggestions, plug/wire on on of the 4 deactivated cylinders I guess. Ahh, I'm sure the dealer will know more then I can guess at. I probably won't bring it in for a month or two, but will update if I hear something.