Tacoma - OVTUNE - VFTUNER - Update Info and Original Development

I occasionally get a slight clunk as what is being described.... it's more like some kind of whiplash on the drivetrain during braking when it downshifts from 2nd to 1st, is the best I can describe it. Its like when it downshifts maybe the tension on the driveshaft momentarily reverses, if that makes sense.

 

Ive run your tune for the past couple months and love it. I know you are kinda of a 1 man team but you really have a brand on your hands. You should really think about providing stickers or start selling hats and shirts and market your brand. A great place to hit it big would have been Toyota Jamboree this past weekend in Texas. You could really take off with a business line and expand into other toy lines like the 4runner and Tundra which I know is a big thing down in Houston, Texas by DAP tuning.

 

I love 1.04, 91 octane, so this is not a complaint. Simply more info for those interested.

I had the clunk, as described by those above, from day one with the OEM tune. It disappeared with the various tunes available from OVTune prior to 1.04. Initially no clunk with 1.04 either, but it has developed, intermittently, now that I have several hundred miles on 1.04.

I am in the camp that believes that it is related to the torque converter disengaging.

Frank

 

I've had the clunk and the rumble strip while braking from day one. The rumble strip is disappearing and the clunk is getting worse. For me, not tune related.

 

i have brought this up before before but had little feed back.but with the recent rash of clunking complaints i will try again.
When operating any machinery smooth transition of moving parts is key for longevity.
The jolting some drivers are experiencing is from DFCO kicking on and off and is most pronounced in MTs because we have more feel.your costing along the Hwy let off throttle DFCO kicks on not to bad slight jolt as engine shuts down but just touch the throttle and BANG engine comes back to life and sends jolt through drive line

for the AT it seems most complaints is coming to a stop. so your decelerating to a stop, your engine will be off,as the revs drop to around 1000 rpm,the engine will fire up again causing counter rotation in drive line then clunk.

if OVTUNE Can kill the DEFCO to make option for us to try ,while this will lead to higher fuel consumption it will give best throttle by cable feel..

 

"for the AT it seems most complaints is coming to a stop. so your decelerating to a stop, your engine will be off,as the revs drop to around 1000 rpm,the engine will fire up again causing counter rotation in drive line then clunk."

Had not considered this, but it sounds like a reasonable explanation. Probably fixable. But still, odd that it exists in one OV tune, but not another.

Frank

 

That's plausible, I like it

 

is the "clunk" you guys are feeling somewhere around 10mph or so, when the truck downshifts into 1rst right about 1000 rpm when braking? I feel this on my truck it's the feeling of the downshift, but it doesn't feel like a "clunk." I'll double check some of the previous posts, I'm trying to reproduce the scenario on my truck

 

Yeah, I'd say that's about right, I can feel it and occasionally hear a bit of a clunk sound from the drivetrain. In my case, it is just a slight annoyance, nothing I'm to concerned about, but sounds like it more pronounced in others trucks.

 

For me it varies. Usual it's more of a loose bump - like downshifting while slowing down in a manual transmission but not rev matching. I've gotten used to it, but once a month it feels far more metallic - more of a crunch.

 

Interesting thing - I had more of a shift clunk before the OVTune when slowing to a stop at a light or stop sign. When the truck warmed up enough the clunk stops altogether. Since the tune was installed on a warmed up truck I have no idea how the OVTune will perform on a cold start and run. Will do now and report back.

 

okay this makes sense, the ECU does not try to match the or hold engine speed to make a "seamless" downshift when you're decelerating

 

I can say it seems like the OVTune brings out the potential of the 4.88's. I don't know. I haven't really tried to hot dog it yet.

Unfortunately, I cannot say what the low end OVTune feels like without the 4.88's because the gears were done first so I really have no base for comparison.

 

Mat I don't think it's 2nd to 1st, I think it's third to 2nd downshift?

 

According to @dcz108, it is a 3-2-1 shift in quick succession that causes that clunk/thunk

 

Ok so I know these questions have been probably answered on this 894 page forum manifesto but I have to get some answers to install my OV tune I received a few weeks back. I know Mat is super-busy to answer my emails for help installing but tomorrow is my first day off of work in the past 31 days so I would like to install tomorrow if possible. Here’s a couples screen shots of the errors I’m receiving:



I need to get Mat my dongle info for its serial number to authenticate it to proceed. Any help would be greatly appreciated.

B

 

Disable windows defender, that's the issue,

I'm going through emails right now if you'd like more help via email

 

Yes, that sounds right. But I would add that it actually bumps the truck forward, and I have to apply more brake in order to stop where I had planned to.

Frank

 

"Mat I don't think it's 2nd to 1st, I think it's third to 2nd downshift?"

Definitely second to first for me. And it goes away when the truck is warmed up.

Frank

 

Thought your truck was in shop for twin turbos? :-O