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Discussion Starter #1
I drove my truck down to FLA this summer and shortly after I got here the Truck would start out in 3rd gear in drive. 2nd will work if you select it but there is no 1st or 4th. Fluids were fine oil and tranny oil were clean as could be. Scanned the codes and got a P0788. Shift/ timing solenoid high. I figured that The 1-2 shift solenoid was bad so I dropped the pan and replaced it. Poured in a jug of lucas with some new fluid but still doesnt work.

After that I was reading 355 and came across an ignition switch issue that might be causing it so I replaced that also. Checked the fuses under the hood everything looks good but nothing has worked.
 

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how many miles on the truck how many times has the fluid been changed ?
 

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Discussion Starter #5
Its an 04 with 60000 on it and the fluids been changed every 5 to 10 thousand. It also gave me a low voltage code too. Would that have anything to do with it?

Also when taking out the servo, what would I be looking for??
 

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Discussion Starter #7
I took out the servo and put it back in, everything looks great. I did replace it with a corvette servo a while ago but its drove great since and by the looks of it, it isn't the problem. All the seals and bands look brand new.

I'm thinking it could be electrical since I got a low voltage code when it was scanned. Anybody agree??
 

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Yeah that makes sense. You have some solenoids in the trans which could mess up the shifting if not activated properly.
 
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