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Discussion Starter #1
Recently I am having a problem with my tranny not shifting properly from second into third. Tranny is a suncoast stage 4 with a 1056 converter. The truck seems to shift perfectly when it is cold, but once the tranny temp heats up, it feels like the truck loads up in second and then shifts hard into third.

Checked the fluid levels and they are all fine. Run all amsoil synthetics.

I also have a clunk when I shift the truck from park into reverse, so I imagine it's the u joints which I will be changing this weekend. Somehow I think my tranny shift problems go beyond the u joints.

Tried several different tunes and it makes no difference.

This is starting to irritate me. :mad:

Any ideas?
 

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have you tried changin your fuel filter. haveing a clogged fuel filter sometimes acts like you have a trans issue but you might not.
 

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Discussion Starter #3
No, but that might be the next step....running out of options and patience.
 

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thats a pretty common thing. good luck
 

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also, when is the last time you changed the tranny spin-on filter?
 

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Discussion Starter #6
Update on my tranny.

Changed all the filters....no change. Running Amsoil Torque Drive fluid in the tranny.

Truck feels like it is slipping between the 2-3 shift. Feels like it loads up and then shifts hard. It is becoming extremely frustrating as the truck is no longer fun to drive.


I took it out last night with my buddy to show him the problem and to pinpoint the actual shift point where the problem happens. It was 4 degrees celsius and I could not get the truck to shift poorly between 2-3 the whole 45mins we were out. It did however slip when I went to pass a transport.

Today I get into my truck and I notice that my speedo is all f#$*ed up as it reads 100km at idle. This happened last night during my test trial. The first shift today from 2-3 was the signature load and bang.

Can anyone offer some insight as to why this occurs? I am getting no codes. Could my tcm be on its way out? Torque converter faulty? Tranny fluid improper? I am grasping at straws at this point.

I am three seconds from ripping it out and sending it away to cali as I live in small town canada with no shops close by. Sadly, I have already spent several thousands on this tranny.
 

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Discussion Starter #7
Would a faulty TCM make my shifting pattern so awkward? My truck shifts fine sometimes but horrible at other times. Also thought about maybe the truck isn't getting enough fuel with the tune I have on it (100hp tune).

Thoughts?
 

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Check the output speed sensor, and the wiring going to it, as well as the connectors. TCM failure is VERY rare.

Do you have a scan tool or EFILive so you can monitor tranny speed sensor readings, as well as the VSS signal? (vehicle speed sensor, the one on the top of the transfer case)

ben
 
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