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5.9RuCon

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Discussion starter · #1 ·
Cruising on Freeway set at 70mph'ish and going up a steep grade, about 2/3 the way up RPM's go all over the place, the entire rig shakes violently, and check engine light comes on.

Reach the top of the hill, RPM's settle, check engine goes off, and I stop swearing.

Next hill, 2/3 the way up...same shimmy, RPM's and check engine light. This has only happened climbing steep grades with cruise control set.

It's a 5.9 with a 46RE tranny, is this the lockout/up? It never down shift into a lower gear, though it was pulling up the hill with ease.
 
Discussion starter · #4 ·
Fluids were all good, full and clean. I was under the impression you could only pull codes if the check light stays on? Both times the light went out as soon as I leveled back out.

I figured it was the tranny wanting to down shift, but the cruise control not letting it?
 
It wouldn't be a cruise problem, that system only controls throttle.

I was thinking the torque converter was trying to unlock, which would occur before a downshift. Try doing the same hill with the OD button pushed. I haven't seen the hill, but I'd guess with your niner, you should be able to power up the same hill in 3rd gear without a TC unlock. And theoretically not experience the problem.

I think all codes are stored for for so many startups (like 50?), then they are cleared.
 
Discussion starter · #6 ·
I don't use CC much, and rarely does the 5.9 have to downshift up a hill. I just wanted to make sure this wasn't an underlying issue of a more serious problem.

I'll try and get the codes pulled.
 
i know you already probably did, but make sure to check the tranny fluid when idling in NUETRAL, not park, unless your dipstick says otherwise. It makes a big difference in the reading. This goes towards everybody, read your dipsticks...i didnt at first and ran the wrong level in mine for a while.
 
Discussion starter · #8 ·
Yeah I always make sure its warmed up, then I run through R N D 2 1 and back to neutral before checking the fluid.
 
Pay the two dollars and buy a full tank of premium fuel the next time you plan to climb the grade. This should help you figure out whether or not it is engine ping or not.
 
Discussion starter · #10 ·
The 5.9 requires premium because of the spark advance, and this was definitely more than pinging. It shook the entire rig to the point I thought 'ish was going to start falling off.
 
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