2-3 shift flare seemingly fixed w/overfill - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

Robmnrd · 02-20-2020, 05:32 PM

Hey guys, before getting into this thread (which serves purely to recount my personal situation) I want to say that I would not *suggest* doing what I did, but that as adults, anyone who reads this thread is free to make their own decisions.

So for kind of awhile now I have had a 2-3 shift flare when in Sport non-manual mode when shifts were commanded above 5000rpm (aka high-load/rpm, performance driving). Didn't happen in D, and didn't happen in Manual. After doing a bunch of searching, the three main culprits I found through the internet were: poor transmission tuning (for cars that are modified and tuned, obviously), a genuine internal part failure (could be any number of a bunch of things), or...simply low fluid level.

More research suggested that the third option was actually highly likely because apparently GM can't reliably fill these transmissions from the factory. I found numerous stories of people checking their fluid level themselves because their dealer refused to "open" the transmission because it is a "closed" transmission with a 100000 mile service interval.

So basically GM frequently sent out Transmissions that were anywhere from 1-3 quarts low, "sealed" the transmission, and won't let anyone do basic maintenance work on them...in high performance vehicles that see high-stress duty...

Given the simplicity of adding fluid to the transmission, I figured I would give it a shot as a sort of diagnostic for my problem. Worst case scenario I still have a problem and need to pull the transmission and pay 1000s of dollars for a rebuild. Best case scenario I fix a mistake on GM's part and prevent damage from occurring...for 40 bucks. I'm not under warranty, I've got some modifications, made sense to me to try it.

So I took it to a transmission shop (normal quik-lube and Valvoline oil change places won't touch it, neither will the dealership, obviously...) and told them I wanted the fluid level checked, topped off, and one extra quart added in on top of that (the extra quart is from my internet research suggesting that under hard driving conditions with high G forces in multiple directions, you can actually starve the pump of fluid even at GM-spec "full"). The guy threw it on the lift, and when all was said and done (very quick process and I watched him/chatted with him while he did it...) it took 3 quarts of fluid. I don't have a *single* leak/spot under my car/in my parking space at my apartment. The underside was *bone-dry*. I've never smelled anything suggesting burning fluid. So with my requested 1 extra quart on top of topping off the transmission, we can deduce that GM had underfilled my transmission by 2 quarts.

I paid the shop, took the car out, and literally immediately noticed a difference in how the car felt even at low speed/load. It was like it was "smoother"? That's the only way I can describe it. Multiple WOT runs through 1-2, 2-3, 3-4 gear shifts in all driving modes proved to have perfect shifting without a single hiccup, zero shift flare, and without noticeable strange noises or smells or anything.

I am quite pleased now in that it seems like *for me* there was a very easy and cheap fix for my 2-3 shift flare. All it took was 3 quarts of fluid and 30 minutes of total time.

I am worried, though, because the difference in how the car "feels" suggests to me that running multiple quarts low (thanks GM) may have caused some other underlying problem that I now noticed with the back-to-back driving comparisons at low load/speed.

I am hoping that I don't have something major arise from the fluid level being low for awhile...hopefully I got to it "in time" so to speak.

I know this is a bit of a long thread, but I felt like telling this story may potentially benefit someone else in the future.

silversleeper · 02-20-2020, 10:15 PM

Thanks for the heads up. Doubt it did much damage. You could pull the pan and look for residue if you really wanted to and even if there is some it is "normal".
I've driven cars so low it acted like it was in neutral then catch into gear. Added fluid and they were ok for years (except leaking seals still leaked of course). Good thing you had them do that and not take it to many shops that would have charged for some $$$ "repair". New trans or something that wasn't needed.

Robmnrd · 02-21-2020, 01:53 PM

Quote:

Originally Posted by silversleeper

Thanks for the heads up. Doubt it did much damage. You could pull the pan and look for residue if you really wanted to and even if there is some it is "normal".
I've driven cars so low it acted like it was in neutral then catch into gear. Added fluid and they were ok for years (except leaking seals still leaked of course). Good thing you had them do that and not take it to many shops that would have charged for some $$$ "repair". New trans or something that wasn't needed.

I appreciate your positivity and will definitely keep my fingers crossed that I end up okay as well!

I had some previous threads on here about doing some power adding mods to the car, but immediately shelved them when I first noticed this issue. If, after a few weeks of driving, there are no issues and the shift flare remains solved, I think I can look to move ahead with doing some more fun-mods to the car.

silversleeper · 02-21-2020, 08:43 PM

Quote:

Originally Posted by Robmnrd

I appreciate your positivity and will definitely keep my fingers crossed that I end up okay as well!

I had some previous threads on here about doing some power adding mods to the car, but immediately shelved them when I first noticed this issue. If, after a few weeks of driving, there are no issues and the shift flare remains solved, I think I can look to move ahead with doing some more fun-mods to the car.

First mod I'd do then is add the JRE Jannetty dipstick to the trans. Mine I got from him isn't marked very deep so hard to read, but that's where I'd start as my first mod. I think it was about $80.

Dave Karl · 02-22-2020, 10:22 AM

I installed a transmission dipstick from Jannetty Racing. Checked the fluid level and had to add a quart and a half to get it to register on the dipstick. I didn't have any problems with the tranny shifting and I had the dealership flush and refill the tranny but it was still a quart and a half low.

tstodii · 02-24-2020, 11:15 AM

Quote:

Originally Posted by Dave Karl

I had the dealership flush and refill the tranny but it was still a quart and a half low.

This could be b/c some "techs" are lazy. They will read the spec sheet that says x number of quarts, toss it in, and close the hood without checking levels. I've seen it happen many times :( Harder without a dipstick to check your work. Blind leading the blind

02-20-2020, 05:32 PM	#1
Robmnrd Drives: 2013 ZL1 Join Date: Aug 2018 Location: Texas Posts: 111	2-3 shift flare seemingly fixed w/overfill Hey guys, before getting into this thread (which serves purely to recount my personal situation) I want to say that I would not suggest doing what I did, but that as adults, anyone who reads this thread is free to make their own decisions. So for kind of awhile now I have had a 2-3 shift flare when in Sport non-manual mode when shifts were commanded above 5000rpm (aka high-load/rpm, performance driving). Didn't happen in D, and didn't happen in Manual. After doing a bunch of searching, the three main culprits I found through the internet were: poor transmission tuning (for cars that are modified and tuned, obviously), a genuine internal part failure (could be any number of a bunch of things), or...simply low fluid level. More research suggested that the third option was actually highly likely because apparently GM can't reliably fill these transmissions from the factory. I found numerous stories of people checking their fluid level themselves because their dealer refused to "open" the transmission because it is a "closed" transmission with a 100000 mile service interval. So basically GM frequently sent out Transmissions that were anywhere from 1-3 quarts low, "sealed" the transmission, and won't let anyone do basic maintenance work on them...in high performance vehicles that see high-stress duty... Given the simplicity of adding fluid to the transmission, I figured I would give it a shot as a sort of diagnostic for my problem. Worst case scenario I still have a problem and need to pull the transmission and pay 1000s of dollars for a rebuild. Best case scenario I fix a mistake on GM's part and prevent damage from occurring...for 40 bucks. I'm not under warranty, I've got some modifications, made sense to me to try it. So I took it to a transmission shop (normal quik-lube and Valvoline oil change places won't touch it, neither will the dealership, obviously...) and told them I wanted the fluid level checked, topped off, and one extra quart added in on top of that (the extra quart is from my internet research suggesting that under hard driving conditions with high G forces in multiple directions, you can actually starve the pump of fluid even at GM-spec "full"). The guy threw it on the lift, and when all was said and done (very quick process and I watched him/chatted with him while he did it...) it took *3 quarts* of fluid. I don't have a single leak/spot under my car/in my parking space at my apartment. The underside was bone-dry. I've never smelled anything suggesting burning fluid. So with my requested 1 extra quart on top of topping off the transmission, we can deduce that GM had underfilled my transmission by *2 quarts. I paid the shop, took the car out, and literally immediately noticed a difference in how the car felt even at low speed/load. It was like it was "smoother"? That's the only way I can describe it. Multiple WOT runs through 1-2, 2-3, 3-4 gear shifts in all driving modes proved to have perfect shifting without a single hiccup, zero shift flare, and without noticeable strange noises or smells or anything. I am quite pleased now in that it seems like for me* there was a very easy and cheap fix for my 2-3 shift flare. All it took was 3 quarts of fluid and 30 minutes of total time. I am worried, though, because the difference in how the car "feels" suggests to me that running multiple quarts low (thanks GM) may have caused some other underlying problem that I now noticed with the back-to-back driving comparisons at low load/speed. I am hoping that I don't have something major arise from the fluid level being low for awhile...hopefully I got to it "in time" so to speak. I know this is a bit of a long thread, but I felt like telling this story may potentially benefit someone else in the future.

02-20-2020, 10:15 PM	#2
silversleeper Big Crow Drives: '13 ZL1 Join Date: Mar 2017 Location: California Posts: 1,493	Thanks for the heads up. Doubt it did much damage. You could pull the pan and look for residue if you really wanted to and even if there is some it is "normal". I've driven cars so low it acted like it was in neutral then catch into gear. Added fluid and they were ok for years (except leaking seals still leaked of course). Good thing you had them do that and not take it to many shops that would have charged for some $$$ "repair". New trans or something that wasn't needed.

02-22-2020, 10:22 AM	#5
Dave Karl Drives: 2013 Camaro ZL1 Conv. Join Date: Apr 2016 Location: La Crosse, WI Posts: 77	I installed a transmission dipstick from Jannetty Racing. Checked the fluid level and had to add a quart and a half to get it to register on the dipstick. I didn't have any problems with the tranny shifting and I had the dealership flush and refill the tranny but it was still a quart and a half low.