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While cruising at about 40 around a curve on the freeway my transmission somehow found neutral! Every gear simply left all at once. No pop, no jerk. Nothing. Engine just started freely revving. Had it towed to the local shop. They tell me I need a new transmission. I pay for one that came with a 3 year warranty. They pull the old one and put the new one in. Same exact problem still there! What am I missing?
 

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check engine light on?

fluid leaks?

shifter came out of gear? look under and see if you can see the shift rod attached.
 

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check engine light on?

fluid leaks?

shifter came out of gear? look under and see if you can see the shift rod attached.
No leaks, no check engine lights, I got under it and checked the shift linkage and it was good. Even had my girl shift while I was looking and all mechanical parts moved. Could even hear the transmission mechanically go into gear. There was a ticking noise like when you need oil and you can hear your lifters, but that was all that was different
 

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First of all you need to find a new "local shop", the place you had work done is incompetent.
It sounds like the transfer case went into Neutral.
This’ll will def be last time I go there. Transfer case went to neutral? Is that a common problem?
 

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AWD Transfer Cases can do this - I've repaired a bunch of them - but yeah - the idiots who took you for a ride should be dragged into court at least.

Did you get a full refund?

BTW---> do you have mismatched tires? Just askin'................
 

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AWD Transfer Cases can do this - I've repaired a bunch of them - but yeah - the idiots who took you for a ride should be dragged into court at least.

Did you get a full refund?

BTW---> do you have mismatched tires? Just askin'................
I never picked it up. The shop still has it. The owner is telling me that the pump was bad in the transmission they ordered and a new one is on the way. I think I'll not mention the transfer case until they install the second new transmission. I asked what codes were showing when I checked and he looked at me like I was crazy! Smh. BTW tires are the same. I'm running 24's with the belltech 2/3 inch drop kit
 

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Wait a minute... they're just an R&I shop?

Don't they bench their own transmissions? That's like going to an expensive Italian restaurant and finding out they have a dumpster full of empty Chef Boyardee cans
 

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My transmission went out at a red light in the rain with 205k miles on the 2002 Envoy. Took it to Aamco, 3 days later and $3k less in the bank account and she is running like a stallion again....when you don’t know how to repair it, take it to a professional that specializes in that repair....
 

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Anyone who experiences his sort of problem... just do this one simple test before you go to places with double As in it's name.....

Start the engine, shift into any forward gear whether it goes into any gear or not .... then rather rapidly put it into PARK.

If you get a LOT of noise... ratcheting, grinding, etc....... you are in NEUTRAL in your transfer case or someone stole your driveshaft.

Just put it back into NEUTRAL to make the noise go away.

Don't worry because it won't actually get into PARK until the output shaft gets slow enough (it likely won't) ... just before it stops (which it prolly can't) ..... if it DOES slow down that is... which won't happen if the engine is still running,

You'll have to shut off the engine and just let things come to a stop in the transmission.... but your vehicle can roll away if you don't use your PARKING BRAKE!
 

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He called me yesterday and told me to come take it for a test drive. I drove it home and plan on going back in the morning. Not sure, but I think it's good. Smelled like I was getting some burn off from a fluid I couldn't identify, but I'll let them figure it out. Can someone tell me about this trans cooler I keep reading about?
 

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Yeah ---> Working under a car, it's not unusual to get some ATF on the exhaust system - it'll burn off OK. It should stop after a short while.

Following is a short lecture on transmission coolers; their installation, right or wrong......... and this may be TL;DR to some people, but I can copy/paste it again into any posts concerning transmissions, transmission coolers and overcooling a transmission... later on!

You've been warned.

_

Since our vehicles have a rather oddball cooling system configuration, we don't get the full advantage of regulating the ATF temperature as the transmission really needs.

From the factory it is capable of protecting itself from running too hot (bad) or almost running too cool which is really BAD.

However, an add-on auxiliary transmission cooler can be a great addition to your car.
  • BUT - there are rules as to where to put it and if you do it wrong, you can cause more grief at the same time think you've 'helped' your transmission while you are actually harming it.
Inside the radiator, is a 'heat exchange' unit that take heat out of the transmission fluid, true. This is incorrectly called: the transmission cooler.

It is not only a 'cooler' but a 'heater' too, so part-of-the-time it cools and other times it heats the ATF.

It's primary purpose is that it keeps the ATF temperature to about: 200F. This is coincidentally that same temp the engine likes. The thermostat holds the engine to 200F, so the heat exchange unit in the radiator is a good source of the right temperature for the transmission.

The best idea for improving the life of your transmission is to allow it to run at the temperature where everything was designed to run. That can be done by taking some of the heat FROM the engine and raising the temperature of the transmission to 200F. This is a benefit to both the trans and the engine.

Problems start by allowing the trans to get over that preferred temperature.

This can come from:
  • Working the transmission hard eg: towing, carrying heavy loads across the Sahara Desert at high noon at 90MPH.....
  • Not letting the TCC hook-up for the higher percentage of operation by manually shifting the unit which up to a point takes the TCM Thermal Safety system out of the loop.
  • Ineffective cooling fan/insufficient ram-air effect from driving slowly with a big load and/or a defective electric fan. ,
  • etc.
OVER-cooling a transmission is just as bad as overheating ---> and it can be caused by:
  • Adding an auxiliary ATF cooling system that keeps the unit too cool
  • Putting this add-on cooler in the wrong side of the transmission cooler lines
  • TOTALLY bypassing the built-in radiator heat exchange unit and just running the add-on cooler (this is the worst thing to do for several reasons)
If you want to do an aux-cooler installation to help keep the engine and ATF temperature from going too high - put the add-on cooler into the hottest transmission cooler line before it gets to the heat exchange unit inside the radiator.

That way, you'll reduce the thermal load on the engine's cooling system by not dumping excessive heat INTO the radiator, but allowing the radiator to reheat the ATF to the correct temperature.

This also lowers the thermal load on the radiator-engine cooling system by taking excessive heat out of the ATF before it gets to the radiator-heat exchange unit.

Then the heat exchange unit inside the radiator will reheat the ATF to the correct temperature of approx 200F - the optimal transmission temperature.

____

Finally ---> you'd be surprised to find that transmissions need rebuilding for over-heating and also for over-cooling. Keep them too cool and the seals get hard, refuse to seal correctly, burn clutches and bands and generally destroy a transmission too.

IOW - running the unit too cold or too hot are both wrong.



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