Normal...I doubt but who knows?

[Crankme69]

Left work today with the 6.5, had to pull out & gun it some to get into traffic, the truck took off just fine, but then did not want to shift?

The idle would drop right back when I let off the throttle...but when applying it again still did not seem to want to shift like normal??? So being as though I have read a little about all the electronics with this auto trans, I opted to shut off the motor while coasting and restart it, all was fine after that???

The fluid is clean with NO smell, now my rig has 196,500 miles on it so anything is possible, the motor & trans was cold, it's about 30F here I think today, I normally let it warm up longer then I did when this happened.

Is this the start of some symptom that I should be concerned about? No codes.

I have not had very good luck changing trany fluid especially on a rig with this many miles, so what would you do?

I have run this 6.5 rig about 3K miles now since purchase with nary an issue with shifting, but it has been cold here the last 2 days, single digits yesterday morn, I had it plugged in, fired right up, barely had to crank it, kinda scared me! No issues yesterday but I did leave it warm up before departure nutta til today???

VERY WEIRD drove home my 50 miles like normal, it didn't miss a beat on the superslap crusing at 70mph...

TIA,
69

 

[Woody35]

when it did not shift was the truck very cold. in other words had you just started the truck up after sitting a long time. my truck after sitting a long time will not shift normally until a few mintutes warming up. most likely to protect the cold transmission

 

[Dieseldad97]

Sounds kinda normal to me. When its bloody cold out, I run pretty slow down the road till the truck wants to shift itself...make sense? When on the highway, it won't go into OD till the temp starts to go up. This can take 3-5 miles.

Hope this helps.

 

[vail426]

I use amsoil ATF and when it gets cold, the truck shifts perfect. I changed to Amsoil years ago . Cheap insurance.

 

[fonecop1]

FWIW. My 95 did this last week when it was cold and had been sitting all day, I pulled over and shut it off then restarted it and then it shifted just fine. When I checked the codes it had an 81, 84, and a 99, the 81 was the 2-3 shift solenoid. I tried to clear it with a scanner and it wouldn't clear neither would the 99. Because of other problems with the idiot lights coming on about 5 or 10 seconds after I turned the key on I replaced the ignition switch and that cleared all problems and codes. My friend is a transmition mechanic and he told me that he had to replace an ignition switch one time on a chevy truck to fix a no shift problem.

 

[Chevylover]

Sounds kinda normal to me. When its bloody cold out, I run pretty slow down the road till the truck wants to shift itself...make sense? When on the highway, it won't go into OD till the temp starts to go up. This can take 3-5 miles.

Hope this helps.

Yep, so does mine, too. Or I let it idle a few minutes to warm up.

Cu,
Sven

 

[Crankme69]

Thanks for the replies All. I should have let it warm up a while and I normally do. Just leaving work and was in a hurry. I'll know better.

Thanks again all...have to see if it happens again, Hope Not!

 

[Matt Bachand]

Watching the tranny temps warm up with high idle while attached to a scanner, it doesn't take much more than 5-7 minutes or so for it to creep up warm... I always let her high idle for a few minutes, usually 10-15 on these cold new england mornings.

If i'm in a rush leaving someones house, it gets a minute blast of 1300 high idle...

 

[JMJNet]

My dad just told me a story about his 6.5 Burb transmission that was acting up when it was cold last week. He went to the trans place and they could not find anything wrong. They said it is normal for the trans when it is cold. You may want to heat up the truck a little.

 

[minisub]

Mine's done it a few times. It was never too cold out, but I had really marginal batteries each time. Always figured it was a voltage issue.

 

[JiFaire]

Like many other things, this is a multi-possibility kind of problem...

- poor grounds/low voltage
- sticking solenoids
- low temps
- ignition switch issues

All of the above (and probably more) can influence this behaviour... when it happens, the real trick is to figure out which one is the problem. Like many other things then, good diagnostics or starting with the cheapest things first are mandatory troubleshooting/repair procedures.

You can mask some things by putting in new batteries, or by using synthetic fluid, but if the basic problems are still there, you need to keep moving up the chain...

: Start with warm-up. It's free.
: Grounds are basic maintenance - should be doing this all the time anyway. Also free.
: Synthetic fluid and/or fluid change - need to do this on regular maintenance schedule anyway - something most people neglect, for some reason. Synthetics are pretty much a necessity if you're playing in Canadian temps
: ignition switch is a PITA to change, so make sure this really IS the problem before tackling it, and make sure you use a genuine ACDelco switch. You only want to do this once.

Jim