[CdnCummin]

So I took my truck to a highly recommended shop in my area because my lights were flickering.I checked my connections, batteries and alternator were less than a year old so I thought a pro could figure it out fast. He did,bad batteries( crappy tire) but on a test drive he lost 2 gears in the transmission! I just bought a NADP Heavy Hauler this summer WTF! NAPC says I had a electrical problem first, it's an electronic trans.... I didn't drive long with the problem, trans light never showed up while I was driving, and I haven't drove at the hp I told NADP I was shooting for. NAPC is talking to the mechanic about it, I hope there gonna warrantee it, i did not wanna buy myself a trans for Christmas. So if in doubt don't b cheap buy 2 new quality batteries.

 

[TransEngineer]

Bad batteries will not kill your transmission. If your system voltage falls too low, the TCM will set a Low Battery Voltage fault, and may put you in limp-in, but that will not kill the trans.

Which two gears did you lose? How does the trans drive now? What does it do (or not do)? No shifts into 5th or 6th? Got any faults or CEL? Does it shift normally 1-2-3-4?

 

[CdnCummin]

Happened to the mechanic on his test drive, when I drove there seemed like it shifted down from 6-5 easier than usual, but I drive 3 different trucks so I could b wrong. I'll b talking to mechanic more today. Get more details.

 

[CdnCummin]

Shifts 1-4 fine no 5 or 6 it just won't shift up after 4, gear ratio code. I didn't get a specific number, mechanic is confident it is a warrantee issue. I'm waiting to hear back from NAPC...

 

[TransEngineer]

Yup, sounds like the OD clutch is not holding full torque. Likely a P0735 Gear Ratio Error in 5th.

 

[CdnCummin]

Thx TransEngineer hope that means good news when the bill comes in, trans seemed great until now told them I was shooting for 650 hp, they were very confident the package they gave me could handle more than that. I don't know the specifics of their upgrades offhand, paperwork is with truck. last dyno was little over 450, I did some upgrades since but haven't run high tunes because I want to tune on dyno to stay within my goals and try to eliminate all smoke possible. Glad it didn't happen hauling family thru the mountains, I'm sure NAPC will take care of it and I won't have any more problems. Still waiting to hear from them...

 

[bob4x4]

So I took my truck to a highly recommended shop in my area because my lights were flickering.I checked my connections, batteries and alternator were less than a year old so I thought a pro could figure it out fast. He did,bad batteries( crappy tire) but on a test drive he lost 2 gears in the transmission! I just bought a NADP Heavy Hauler this summer WTF! NAPC says I had a electrical problem first, it's an electronic trans.... I didn't drive long with the problem, trans light never showed up while I was driving, and I haven't drove at the hp I told NADP I was shooting for. NAPC is talking to the mechanic about it, I hope there gonna warrantee it, i did not wanna buy myself a trans for Christmas. So if in doubt don't b cheap buy 2 new quality batteries.

Sounds like the tech was out enjoying your truck to the point of trans damage............

 

[CdnCummin]

Lol, could b. I enjoy it. He was very well recommended by multiple people, I try to do all my own work unless it causes warrantee issues (trans was pro installed) so when I have to get work done I go to a trusted dealership or well known shop.I'm quite embarrassed my issue was batteries and I couldn't resolve it myself, I don't have aftermarket stereo/starter or other electronics,batteries were new... Should know better by now not to get cheap parts, even if I gotta wait/travel for quality ones.

 

[skinnyvito]

4th gear - limp mode

A few years ago I had a similar problem.

In the winter months, when the engine was cold, my transmission would sometimes go into limp mode and not leave 4th gear. If I shut it off and restarted it, it would be okay. This is a stock truck.

I took it to the dealer and they said it was a bare wire causing this. (It didn't fix anything.)

I put in new Deka batteries. It didn't happen again until last month. I have been cleaning the grounds every place I can and hope to fix this problem.

I don't remember the code this caused.

 

[CdnCummin]

New trans coming, thx NAPC! There's so much info on this site referring to electrical issues, some bypass ECM/TCM when they find a problematic wire, some find a problem in the ignition, it seems to go on. Hope the batteries were the only thing wrong, other than the trans. Hope to have it back for the next sled trip I h8 putting my nice sled on a Chevy then ducking all the way to mountains in case someone sees me!!

 

[skinnyvito]

new trans

I'm glad to hear it's working out for you.