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Changed transmission fluid and dont know where I went wrong


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Hello, first time posting in forum- I've run into a pretty scary issue as I just bought a 2000 silverado 1500 LS z71 5.3L. I bought it used and guy didn't do much upkeep with fluids as I changed oil, oil filter, transfercase fluid, front and rear diff all with oem fluids except for tranmission i used dexron vi / mercon lv by valvoline. When I bought it he mentioned a flutter around 40-50 and it shifted fine when i drove it home. So after changing the tranmission fluid, seal, and filter my truck now revs super high and doesn't shift. First test drive after changing the fluid and letting it run for 30 minutes after i added 5 qt into the trans dipstick where i saw on youtube to add it. and it drove fine but then after 3 minutes or so of driving it almost felt like it has 1st gear but i'd hit the gas and it wouldn't engage into the next gear. I kept checking fluid then added another 2 quarts the following day and let it warm up and now the fluid is still low. when i let it drain when changing the fluid i noticed a small black tab ripped by where the seal goes but other than that everything else looked fine. Park, reverse, drive, N, 3, and 2 all engage fine and the truck takes off on its own when putting into drive but soon as i try to drive and leave my driveway it just revs high and doesn't really move, im afraid to rev  it higher to see if 3rd works but im not sure what it could be? should i add more fluid because i let it drain overnight? when i drove it the mornig after i added the first 5 quarts i drove it hard and was driving fine but then after that seems like everything went downhill i also hear a tiny squeek from when i hit the gas and sounds like a light ticking  noise by the oil pan/ transmission area. No check engine codes only codes i have on my scanner is abs motor freespins. Like I said i just bought the truck so idk what to do i dont have money to put in a new transmission. one thing i did notice when i bought itwas the cigarrette lighter fuse was blown so OBD2 port wasnt working to i put in a new fuse he installed aftermarket lights on it im assuming blew fuse. I can upload a video of it if needed to help diagnose i spent every dollar i have on this truck so im hoping for a miracle. Hope its a fuse or do i have to reset tcm after fluid change? transmission was shifting ok before fluid change, could i have him the pan with something i was struggling to get it off

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That looks like where the transmission filter fits into the transmission. There should be a round seal that goes into that hole. The old one likely stuck to the old filter. Your kit should have included a new seal.

 

If you didn’t seal the new filter the pump is likely sucking air. It’s not going to work well as you found out. Drop the pan and install the seal. That broken bit is a plastic piece. It’s likely ok if it cracked as they can be damaged when seals are removed if your not careful or do not have the correct seal puller tool.

 

 

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Also, you mention having trouble getting the pan off and out. A common issue is for people to screw up the shift solenoids and/or wiring for them.

 

As mentioned above make sure you got the old filter seal out and the new filter seal in place and the filter inserted all the way. Also make sure you got the correct filter for your pan.

 

If the new seal is not seated properly, it can suck air at that point too

 

 

 

 

 

Here's a pic of the seal in place, it's in the process of being removed.

 

**Edit: It won't let me link to the picture, but it's the pic that Black02Silverado has below

 

 

 

 

Edited by txab
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I dropped the exhaust at the manifold to pipe connection to give room to properly drop the pan when I did mine. I believe you will need the deep pan filter. Verify with parts store. Good luck.

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As mentioned above, check all those points.  Make sure the filter you replaced is the same as you took out.  Put them side by side. 

 

You said you added more fluid and it seemed to work. That sounds like you put to much in and the extra fluid allowed to be used if the seal was bad since now it would cover that area.  Overfilled isn't good. So make sure you check the level with it at operating temp and on level ground at idle.

 

Here is my "how to" on my old 2002 Silverado. 

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So I bought the delco kit and came with the transmission seal which i seated properly with the opposite end of a 19mm and filter i pushed in Pretty hard til i felt it pop in i noticed i did slight scratch the side of the whole where the seal goes with my small screw driver but i never ripped off the black tab as  i thought it might be important but from what you guys are saying it isnt anything- i also have a blue drive obd reader and no codes coming up, today i drained all fluid and leveled it perfectly and added lucas oil trans mission fix and its working a little better but still revs high but i noticed today it caught second and third but very late and i gave it gas hard when in 2nd and it shot up to 6rpms so i let off as i got scared- can i upload videos here of my problem- i dont think i made a mistake in installing the seal or filter and im getting no CEL either, wouldnt a bad solenoid cause check engine light? And every time i checked the level the first time i added 5 qts warm it was reading low so in total i added 7 qts and still was reading low fluid on dipstick on level ground- one thing i did notice is theres this clip on the driver side next to the transmission pan that is still plugged in but the clip isnt clipped on but still making contact or i’d be in limp mode right?

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How many miles are on the trans? Certainly looked like a missed shift after 3. Didn’t do this before you dropped the pan? I’ve heard of new fluid forcing a marginal set of clutches over the cliff. May be what’s going on.

 

BTW when you installed the seal I hope you didn’t drive it deeply into the hole? It needs to be driven in only about 50 thou. If you forced it deep into the recess it may still be having trouble sealing.

 

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I’m not 100% on the miles on it but the previous owner said the guy he bought it off had the trans replaced 2 yrs prior- and the seal was flush maybe a small little mini lip flush from it fully seated and the only issue before was when i was driving up hill the reason i changed the fluid was it was acting a little funny when i was driving around for 2 hrs then going up a hill i pressed it and it shuddered a little but other than that it was shifting ok

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Is it worth dropping the pan again or should i just take it to a transmission shop? I need to drive it as my only vehicle- what am i looking for price wise? I spent 5000 on the truck and bought it 2-3 weeks ago or should i just call it now because a buddy mechanic pushed upwards on my driveshaft and its making a clicking noise too when it meets the t case 

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35 minutes ago, bryan george said:

Is it worth dropping the pan again or should i just take it to a transmission shop? I need to drive it as my only vehicle- what am i looking for price wise? I spent 5000 on the truck and bought it 2-3 weeks ago or should i just call it now because a buddy mechanic pushed upwards on my driveshaft and its making a clicking noise too when it meets the t case 

If it was giving you problems before and you have the means, just take it to a transmission shop and let them have the headache. Getting your trans rebuilt is always the best option, its just not always practical for everyone because of cost.  In your case obviously there is some unexplained issues going on, and as you say now you are having other issues, so its probably time.  When I first read your post I was thinking that when you pried out your old filter that you scored around where the filter went in, but wasnt sure it would be enough to cause your issues. 

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Yeah im pretty sure the scratch i put on the hole wasnt too too bad and i lightly sanded the rough part w/ emery cloth so it wouldnt damage the seal and also put trans fluid on it so it would seat nice- the thing is i spent all the money i had on it so im not sure if rebuild would be ideal or anything else i can check to avoid 1000-2000 invested in the truck on top of the 5K I paid for it

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Shudder prior to changing the fluid is a sign things may have been going for a while. Sounds like your in a position that’s tough. Could have u joints or worse going on as well. Did you have a pro inspect it prior to purchase? Ifs just good money to bring in expertise if your unsure.


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