07 SR5 crazy dash lights & speedo

Twice now...good weather, start truck drive for 5-10 mins, all dash lights flash/blink, speedo needle up and down.
Stop, ign off, restart and no repeat...or few mins later same thing. Stop, restart...no power, nada. Then bingo, restarts...all normal.
Replaced both batt terminals, all clean and good, cleaned ground contact. No codes on two different scanners/readers.
Any ideas/opinions?
Bought used several months ago, 110K miles...116K now. Great truck overall, 1st problem.

 

Have you performed a drop test on the battery? (I found out the other day that that's also a thing done with dead 1.5v batteries, don't do that test! ). Perhaps from now on I should say 'load test'.

Although the fact that it restarts after a few minutes points towards a healthy battery and a failing alternator. My 2nd gen cooked it's first alternator around the 110k mark...

Edit: I didn't get a warning lamp either time my alternators failed (I'm on number 3) until they were proper dead.

 

Batt reads 12.5 at rest, 13.9 when running...haven't done a load test yet. Plan to now tho...

 

My battery died shortly before the 1st alternator shat itself, by that I mean that the chap I took it to for rebuilding said that the only usuable part of the alternator was the casing. I had very little warning, besides the 1st battery getting cooked, the new one presumably helped to mask the failing alternator. Otherwise, as I said earlier, there appeared to be nothing wrong.

 

Battery passed the load test...we'll see if clean terminals and shiny ground contacts cure the problem.

 

An observation of both the Tundra and the Lexus in signature is that upon cold start, both shove 13.9 to 14.1V to the battery for 15/20min and by 25min mark the voltage is 13.4 to 13.6v.

Both are pretty consistent. Try a 30min drive and see what it says.

Anything consistently north of 14.2 can boil a battery dry.

I too would be suspect of alternator and suggest a 12V USB charger be plugged into dash for monitoring. Maybe you see something cray cray when the dash lights up?

 

No problem 2day...cold, wet and grey. I'll check alternator output 2morrow. Thanks.

 

Read 14.2 at cold start this morning, 13.56 this afternoon after an hour or so of errands, parts, lunch. No hiccups today..

 

5 days gone and no repeats.

 

Little over a month later still no recurrence.