Engine Damage or Transmission?

I’m very curious to see if the battery is the culprit. I’ll be kicking myself in the ass after spending a grand on a transmission rebuild but I think I’ll just be happy to have it done.

 

Yeah I have to admit it seems weird, but data don't lie! OP please keep us posted on what happens for you.

 

Very interesting

 

Update: tried to start truck day after I re installed the transmission to move it. Battery was dead. Bought new battery. Nothing changed. Still experiencing Problems with transmission.

When the truck is cold there is a slight slip going from 1st to 2nd. As the truck gets hot after about 15-20 minutes of driving. Every gear is slipping roughly. Slipping into neutral, revs high rpm, then catches into gear and knocks violently. When I got it back from the transmission shop he replaced the solenoids and the torque converter. One of the people I did a road test with was a mechanic for years and worked in a transmission shop and he thinks it’s issues in the valve body. Took the truck back to the trans shop and gave him the keys. Let him figure it out.

 

I've seen shorted batteries wreak all kinds of havoc with ECUs to IACVs on just about everything including Chevy, Honda, and Nissan. That's why I change them out after the warranty period expires. It seems like 36-month Advance batteries start breaking down on me at 42 months. I'm looking to switch to Interstate.

 

The battery I was running was a diehard Gold and it claimed to have a 3 year life span. I was well into year 4

 

Your first description of the problem was surging and the second description was slipping two very different things. A surge is an increase in engine RPM with corresponding "push" from transmission or also sometimes described as engine RPM hunting. A slip would be an increase in engine RPM with a corresponding "lag" from the ass end as the transmission looses its drive or push. As for the T-Fluid getting thinner, don't go there as it expands as it gets hotter one of the reasons not to overfill automatics. If you T-Lines to the radiator are compromised with pinched flow or collapsed cooling you could be keeping or trapping more heat in your transmission leading to excessive metal expansion issues compromising the performance or creating a "slip". Don't get your hopes up on the battery judging from the vid it was certainly an event driven problem. I killed my dad's van with a bumper ding. Pinched the line, seemed to drive ok until it got hot and we essentially cooked the transmission.

 

Cool pic - for some reason we all feel better when we at least have it on film

 

It starts as a surging but the longer I drive,15-20 minutes it begins to slip on all the gears. After I see what the trans shop says I’m gunna look into the t lines. Thanks

 

Mebbe some crap got knocked loose and into the valve body? Seems that way, EXCEPT for the temperature related issue, which to me seems to point to a blocked or plugged cooling line.

I imagine when you swapped the trans out you checked really for that Don't want to be a jerk but have to ask if you have done a visual inspection of all the connectors related to the drive train- removed and reseated, checked for broken and or pinched lines/wires?

 

Yeah we did a thorough inspection of everything we could

 

Just went and picked up my truck from the transmission shop again. The guy hooked up his scanner to the transmission and drove it quite a ways on the freeway and through town and there was no codes or indications that he could tell coming from the transmission.

While he was doing his road test a check engine light popped up. Turns out it was for the neutral safety switch. After doing some research it doesn’t seem like my symptoms match that of a failing safety switch but electronics can do funny things sometimes so I’m going to see if my dad’s third GEN 4runner‘s is interchangeable with my first GEN and try that.

 

Right. Again, Symptoms of a failing NSS aren’t consistent with what I’m experiencing but it’s something new. Whether it has something to do with the battle at hand or not the truck popped a code for it so it’s got to be replaced Or looked into at the very least. Just strange

 

You didn’t smash a transmission line cause restrictions?

 

Not to the naked eye no

 

Was the truck having the issues while he had it hooked up? That makes little sense.

If you can get to the switch it's typically a go/no-go set up, you can jumper it if you want to test. I cannot see how that related to the original problem tho.

 

Yeah he drove it with his reader hooked up And said there was no transmission codes and admitted that he experienced the same symptoms I mentioned after the truck had driven for a bit.

 

my dad has a 3rd gen 4runner and the NSS appears to be the same for the two vehicles. i think im gunna pull his after work tomorrow, throw it on my truck and see if it still acts up.
im certainly not expecting any changes but its something to look at.

 

I’m starting to think ECU...

 

Is that sarcasm or a serious question?