Is my transmission going out?

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thecantaloupeman

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It's certainly possible that it stuck in 2nd or 3rd, but it's not likely. It's also possible that the converter failed, but it's almost impossible for it to fail intermittently. My money is on an engine problem. Not trans.
Joe
Well I took it in for a free inspection in the shop and they noticed some vacuum leaks and said the intake gasket might need to be replaced.

They said the trans fluid looked red and clean and advised not to flush the fluid because it could remove metal or something and cause the clutch to fail and the tranny to go out.

I’m gonna see what their estimate is for the repairs and possibly have them do it so it will be over with. I need the truck to run good so I can drive to work reliably. Plus they are a new shop in town and I want to see how good they are.


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80BrownK10

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If the fluid is red and clean I wouldn't worry so much about that going out story. I'd drop the pan and refill and filter change. What there talking about is one with very dark fluid or that has never been changed in like 100-200k miles. The fluid is full of metal which actually is your friction disk (clutches) metal and the fluid has enough grit in it to keep the trans working, when you flush it, it removes all that metal and fluid is slippery again and then the trans will start to slip soon after. At least this is how I always hear this problem explained. But if the fluid is "red and clean" if it were me I'd drop the pan and change the filter so that I had a baseline for it's maintenance.
 

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Do you have some joker buddy who jammed a potato up the exhaust pipe?
 

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Well I took it in for a free inspection in the shop and they noticed some vacuum leaks and said the intake gasket might need to be replaced.

They said the trans fluid looked red and clean and advised not to flush the fluid because it could remove metal or something and cause the clutch to fail and the tranny to go out.

I’m gonna see what their estimate is for the repairs and possibly have them do it so it will be over with. I need the truck to run good so I can drive to work reliably. Plus they are a new shop in town and I want to see how good they are.


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So now the fluid is red and clean? You just said it was tested and was black...

What you talking bout Willis?
 

1987 GMC Jimmy

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^^^ This and I’m wondering what your vacuum reading really was. They may not have even gotten a reading. If they saw two or three leaks and sprayed a combustible around the intake edge to see if the idle speed changed, that maybe all they did. I don’t know. The skeptic in me says vacuum issues are fairly easy to deal with, and an intake job bills more than it’s worth. Plus, I wouldn’t take out the first bolt before I was positive every leak was dealt with, and I had a baseline vacuum reading for when it was running normally and one for when it was running poorly. It’d have to be a pretty significant drop to warrant messing with the intake, and I’d exhaust everything else before caving into replacing the gasket set.
 

thecantaloupeman

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So now the fluid is red and clean? You just said it was tested and was black...

What you talking bout Willis?
I thought I remembered it being really bad, but I was thinking of brake fluid. I went back and looked at the inspection from a while ago. My transmission fluid seems to be fine. I didn't get any more info on vacuum leak and they didnt even mention it on the report so i'm confused why they even mentioned I had vacuum leaks. I didn't get an estimate for the intake job. I want to know where my vacuum leaks were now. I honestly have no clue at this point what it could be but it hasn't happened again.

I did however have an incident where I turned my key and they car didnt crank. New battery and it wasn't dead. Left it for a hour and a half and came back and it started no problem. I don't know if this is related or not, but it could be. Although I'm thinking this is a starter issue because it never did sound too great. I have a feeling it is going out.
 

1987 GMC Jimmy

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Do you hear a click, or is nothing happening? Doesn’t sound too great? Spins slowly, grinds, or is it making a totally weird noise? I wonder if your battery cables are succumbing to the “green death,” and it’s time to replace them. Or your battery lugs are either worn, corroded, or loose. Also, it’s important to make sure your grounds are there and in good shape.
 

thecantaloupeman

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Do you hear a click, or is nothing happening? Doesn’t sound too great? Spins slowly, grinds, or is it making a totally weird noise? I wonder if your battery cables are succumbing to the “green death,” and it’s time to replace them. Or your battery lugs are either worn, corroded, or loose. Also, it’s important to make sure your grounds are there and in good shape.

I don’t remember if I heard a click or not, but the starter sounds like it continues spinning after the car starts. I hear it sorta winding down after it finished starting the car. I don’t think that’s normal but I always thought it was a bit weird. The battery cables might be due for a replacement as well.


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varmit86

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Your transmission uses a vacuum modulator on the side of the transmission to shift if it is low on vacuum it will stay in the lower gear and the motor will over rev seaming like the motor is racing but the truck is not moving as it should.


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1987 GMC Jimmy

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I don’t remember if I heard a click or not, but the starter sounds like it continues spinning after the car starts. I hear it sorta winding down after it finished starting the car. I don’t think that’s normal but I always thought it was a bit weird. The battery cables might be due for a replacement as well.


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Old direct drive starters can be that way: noisy. I have one that’s relatively normal sounding, and it quits spinning very quickly. I have another that you can hear rev down a few seconds after startup or if you have a failed start, it’ll free wheel for a few seconds, and if you don’t wait for it to stop, it’ll go ‘clank.’

All in all, I wouldn’t worry about that, but if and when the starter starts to go, you can always get a late model gear reduction unit.
 

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the starter sounds like it continues spinning after the car starts. I hear it sorta winding down after it finished starting the car. I don’t think that’s normal but I always thought it was a bit weird.

Nothing really unusual.

Turn key, 'click'...no starter sound = starter solenoid going. They can be easily rebuilt in about an hour.
 

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Just growing this out there, someone mentioned earlier the parking brake. Partially engaged or a sticking cable could cause a similar issue. Due to the design of the drum brakes, it will hold more going forward. When you back up, it would move easier (still dragging) and could loosen up the brakes or cable. It might be worth checking the rear brakes.
 

thecantaloupeman

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Just growing this out there, someone mentioned earlier the parking brake. Partially engaged or a sticking cable could cause a similar issue. Due to the design of the drum brakes, it will hold more going forward. When you back up, it would move easier (still dragging) and could loosen up the brakes or cable. It might be worth checking the rear brakes.
Hey y’all just an update. My truck completely died and won’t start anymore. I have no idea what happened but it almost felt like I ran out of gas. I was sort of sputtering for a while and my engine had like no power and was very quiet. I pulled up to the next red light and sure enough I couldn’t start it again. I don’t know if it could be related to this issue I had before. I don’t even think I have a lead on this so I just sent it into the shop.


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80BrownK10

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What are you missing, spark, fuel?? You need to test for both of those and then start your trouble shooting once you figure what of those your missing. Like if you don't have spark...is it a rotor, cap, is the coil bad, all wires good, wires to distributor, wires to the key switch. Lots of things will make it not run we just need some info to send you the right direction. But if it's at a shop they will tell you what's wrong.
 

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I guess we'll find out later . . .
 

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