Trans shifts weird

[6speedsd]

Ok this will be sort of hard to explain so bare with me. Truck is a 05 with 5R. Every now and then it'll go into like this quick shift mode. Like it shifts before it should. Sometimes if I take off from a stop it'll shift all the way to 5th before 30 mph. 2-3 is usually where I see it the fastest. Like it won't hold in 2nd very long. 3rd shifts sort of hard too. And then at times if I get on it after it has shifted into 4th (or 5th, however you want to look at it), it will hold for a bit then shift to the last gear then OD almost Simultaneously. And what happens with the TC when it shifts into OD? Locks or unlocks? All I know is when it shifts into OD, the truck really takes off. I don't think I have a TC problem, but I'm not all that knowledgable of auto trans. Has GoGo solenoid in it as well, which I'm tempted to take out because 3-5 shift is almost too harsh.

Best I understand the 5R doesn't shift 1-5, it's 1,2,3,5,6, then OD correct? I know this description is pretty hard to follow and I apologize for that. Just can't figure out how to put it to words. I have AE and heard I can watch output speeds and such to see what's going on. But I honestly don't know what to watch, and wouldn't know what the info I got really meant!

 

[6speedsd]

No opinions?

 

[range91]

Od is 6th gear lockup is after that.. I have seen on a few Chevy trucks that the computer will read that it is in 4lo do to either wiring issue or bad switch and make it stack the shifts. I would check the to make sure computer isn't seeing 4lo signal other than that I am not sure... Any codes?

 

[Zmann]

In cold mode the
transmission shifts 1st gear, 2nd
gear, 3rd gear, 4th gear, 6th gear.
When in hot mode the transmission
will shift 1st gear, 2nd gear,
3rd gear, 5th gear (ratio 1.00), 6th
gear. Either way it is still a five
speed unit with six forward gear
ratios available, depending on cold
mode or hot mode of operation.

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not sure what to tell you Hopefully Mark chimes in

 

[Mark Kovalsky]

Best I understand the 5R doesn't shift 1-5, it's 1,2,3,5,6, then OD correct?

OD is 6th gear. They are two names for the same thing. After it is in 6th gear the torque converter will lock.

My guess about the fast shifting is that the computer thinks the trans is in 4x4 low. A wiring harness fault can cause this.

 

[6speedsd]

Hasn't thrown the first code, ever. And it's a 2wd if that matters.

What can I watch with AE, and what would I be looking for?

 

[6speedsd]

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not sure what to tell you Hopefully Mark chimes in

Makes sense. If it matters, it only does this when temps are up. Never does it before its warmed up good. Now, 4th shifts really hard in cold mode though. I had the usual 3-5 flair, so I put the GoGo in. It helped some, but not much. Once I started running a tune from Eric, it holds 3rd and 5th longer, so it never flairs anymore.

Mark,
How would you diagnose a harness issue? Had someone tell me once that a speed sensor could cause the crazy shift pattern, but I don't know if there is any truth to that, and I'm not about to replace sensors just to find out.

 

[Mark Kovalsky]

If you can look at data while driving you need to see what gear the PCM is telling the trans to be in, what vehicle speed is in AE, if it thinks it is in 4x4L, and what pedal position is. I know what these are called in engineering tools, but I never used AE. I don't know what they are called in AE.

Harness issues are diagnosed with a volt/ohm meter and someone that has experience diagnosing harness issues.

 

[6speedsd]

Thanks Mark!

Ok you AE gurus.... Translate those things into AE lingo. What do I need to select? I think I remember seeing a pedal position option, but the rest I'm not sure of. How is all that labeled on AE?

 

[Zmann]

they just had a meeting of the A/E Guru's

Here is the group photo

 

[6speedsd]

Lol!

 

[6speedsd]

Ok guru's aside, you guys that use AE regularly. What parameter should I watch? And what am I looking for when watching them?

 

[Zmann]

Not sure
I haven't had to look at those PID's for any reason
and I wouldn't know the base lines if I did

that is the downside to not having a A/E for Dummies book available LOL

 

[6speedsd]

I agree. For us common folk it's a bit of a learning curve for sure. This forum have taught me alot about what parameters mean and what the data stands for.

I'm sure someone here has used AE to diagnose trans issues though.

 

[Zmann]

Probably

Hopefully they see this thread and help

I have had My A/E for years
Heck the owner even used My truck for the new contribution graph

but I have yet to even skim the surface of what it can do

 

[Mark Kovalsky]

Look for when the computer commands the shift. See if the vehicle speed makes sense. See if the pedal position jumps or increases and decreases steadily when you move the pedal. There also is a parameter to tell if the computer thinks it is in 4x4 low.

 

[6speedsd]

I'll try to check a few of those things tomorrow. Again, thanks Mark!

 

[Zmann]

Mark is the 4x4 scenario a possibility with His 2wheel drive ?

 

[6speedsd]

Mark is the 4x4 scenario a possibility with His 2wheel drive ?

I was wondering this as well. Wasn't sure if programming was generic no matter whether its 2/4wd.

 

[Zmann]

I know you already asked I just wasn't sure if Mark caught that ?