Cant get up to 45mph

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SUBURBAN5

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98 c1500 suburban 2wd ht383/4l60e trans 3 to 4yrs old from gm and motor barely 1 year..//I'm at a lost. Long story short driving home one day and trans acts like it's slipping past 70mph. Today I was driving home and at first the trans wouldn't down shift. Rpms would go up to 4k and then stay there. The truck acted like it was losing momentum and eventually would just stay reved up. When I took my foot off the accelerator. It would shift and lock into gear. As I'm getting closer to home the symptoms got worse. I could barely get to 65mph then 50 then eventually 45mph. I hooked up my scanner and I saw tcc slippage was going to the red. However the engine started going crazy which is why I'm at a lost. O2 sensors out of spec and engine was running lean non stop. Then I got a misfire popping up and some jerking.. finally I chugged home and just parked it in the drive way. Looked at the transfluid and could of sworn I saw some specs of metal. Now I'm gonna take it to a trans shop but my confusion comes from the engine symptoms... can a trans cause the ecm to compensate slippage and make the engine run like ****?? Any input is appreciated
 

HotWheelsBurban

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98 c1500 suburban 2wd ht383/4l60e trans 3 to 4yrs old from gm and motor barely 1 year..//I'm at a lost. Long story short driving home one day and trans acts like it's slipping past 70mph. Today I was driving home and at first the trans wouldn't down shift. Rpms would go up to 4k and then stay there. The truck acted like it was losing momentum and eventually would just stay reved up. When I took my foot off the accelerator. It would shift and lock into gear. As I'm getting closer to home the symptoms got worse. I could barely get to 65mph then 50 then eventually 45mph. I hooked up my scanner and I saw tcc slippage was going to the red. However the engine started going crazy which is why I'm at a lost. O2 sensors out of spec and engine was running lean non stop. Then I got a misfire popping up and some jerking.. finally I chugged home and just parked it in the drive way. Looked at the transfluid and could of sworn I saw some specs of metal. Now I'm gonna take it to a trans shop but my confusion comes from the engine symptoms... can a trans cause the ecm to compensate slippage and make the engine run like ****?? Any input is appreciated
Damn, I think your Burb has been talking to my trucks and @jus10inbrla 's truck. They're all developing crazy transmission issues with brake and engine factors too.
 

SUBURBAN5

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Damn, I think your Burb has been talking to my trucks and @jus10inbrla 's truck. They're all developing crazy transmission issues with brake and engine factors too.
Yeah the truck must be upset with me or something. I'm hoping it's the cap or plugs for the misfire
Geezus that it scary… close to same symptoms of mine. Sudden loss of power fallin flat on its face, sometimes not having enough to take off.. brakes posible lock up..

How did trans fluid level look other than possibly specs of metal
Fluid looked pink, smells a little burnt nothing crazy and after driving around the neighborhood I can get anymore dark specs. I got a white paper towel and wiped the dipstick about 5 times and each time had nothing blackish.... makes me think if I was going crazy the first time. Either way the same trans symptom accurs where at wot it falls on its face ...
 

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1. If the Vortec computer senses engine misfire, it will disengage the torque converter clutch.

2. If the converter clutch is disengaged, the trans is more likely to run hot.

3. If the trans runs hot, it may enter some kind of "limp-home" mode where some gears are disabled.

Fix the misfire first, see what happens with the trans.
 

HotWheelsBurban

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You may have partially answered the question on my crew cab. I was going to replace cap/rotor and plugs; will be ordering them Monday once my paycheck comes in. Also I noticed that this truck doesn't seem to have an external transmission cooler, though it does have the oil cooler and power steering cooler. I would have thought a truck like that (1 ton crew cab) would've had a trans cooler?
 
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