Slipping shifting into 3rd

Drivetrain discussion including Transmission, Differential, Driveshaft, and related items.
v8suprcapric
Posts: 100
Joined: Sun Mar 30, 2014 9:58 pm
Location: Seattle, WA

Slipping shifting into 3rd

Post by v8suprcapric »

Hey my 80,000 mile 9C3 seems to be wanting to slip when up shifting into 3rd when I'm getting on the gas pretty good. I believe the transmission was replaced at some point under warranty. I still have almost 2 years/30,000 miles left on the extended factory warranty. Think this could be the start of a failing transmission?
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1987 Landau (383 stroker, vortec heads, 700r4, posi rear, Bilstein shocks, Eibach springs, Bassett 15x8, BFGoodrich 275/60, 9C1 speedo)
2011 9C3 (K&N CAI, Weldcraft widened 18x9 factory steelies, Bridgestone 285/35)
xcidmigs
Posts: 783
Joined: Fri Feb 13, 2015 8:12 pm
Location: SE PA

Re: Slipping shifting into 3rd

Post by xcidmigs »

have you changed the trans oil ever? If not might be a good first step
Arcticolds442
Posts: 25
Joined: Thu Dec 17, 2015 1:30 pm
Location: Middle Tennessee

Re: Slipping shifting into 3rd

Post by Arcticolds442 »

I have the same thing happening. Mine has two or three RPM "flairs" at WOT in 2nd gear before the shift. I've got 90k on mine, and the local Chevy dealership looked at it and denies its a problem, but never charged me for diagnostic work, so they either didn't look at it real close or couldn't figure out what the problem was, so they left it alone.

I haven't changed my fluid since I got my Caprice a year ago, and I doubt it got changed prior to it's retirement from the fuzz force. I'll start there and report back.
2012 9C1 DD - stock for now
'72 Olds 4-4-2
'65 AMC Rambler - LQ4/T56 work in progress
"No Bucks Given" '84 VetteKart
'65 Cutlass
smwalker
Administration Staff
Posts: 2201
Joined: Mon Jul 29, 2013 1:44 am
Location: Azusa,CA

Re: Slipping shifting into 3rd

Post by smwalker »

I read the deeper pan from the CTS prevents flares.

Parts Info:

2 Gallons AC Delco Dexron VI Automatic Transmission Fluid
AC Delco Part Number: 10-9030
GM Part Number: 88861954
$23.64 a gallon thru Amazon.com - Free Shipping

Transmission Filter from the Cadillac CTS and Many Trucks (Wide mouth)
GM / AC Delco Part Number: 24236933
$28.79 thru RockAuto.com - Bit Cheaper on Amazon.com

Transmission Pan from the Camaro/Cadillac STS (Deep Pan)
GM / AC Delco Part Number: 24250062
$22.79 thru RockAuto.com - Best price I found

Transmission Pan Gasket (can reuse old one if not to many miles on it)
GM / AC Delco Part Number: 24224781
$12.00 Thru RockAuto.com - Only $6.00 shipping for 3 items.

Info: viewtopic.php?f=17&t=821&#p7418" onclick="window.open(this.href);return false;


Explination from Car Modder in case it gets lost, that site is going down piece by piece:
The 6L80 Automatic Transmission fitted to Holden Commodore V8 models (And export versions of this vehicle such as the Pontiac G8, Vauxhall VXR8, and Chevrolet Caprice, Chevrolet SS) features a transmission sump unique to these model vehicles.

The standard Holden fitted sump is a low profile model fitted primarily to allow for greater ground clearance than the usual sump fitted to other models with the 6L80 Transmission such as the Chevrolet Camaro.

Although this increases ground clearance, it also has the undesired effect of reducing the amount of transmission fluid capacity of the transmission.

This has the flow on effect whereby with the reduced transmission fluid level, it is more likely for the transmission to to experience transmission fluid starvation under situations such as harsh braking, acceleration, or high cornering forces.

This fluid starvation will result in transmission gear flaring on gear shifts, slow gear changes, and poor cold temperature performance.

The solution to this is to fit the larger, deeper transmission sump, and the longer (larger mouthed) transmission fluid filter from the Chevrolet Camaro model (That uses the 6L80 6 Speed Automatic Transmission).
This allows for the transmission to hold an extra 2 Litres of transmission fluid, as well as allowing the transmission fluid pick-up to sit lower in the pan. (Reducing the likelihood of transmission fluid starvation when braking, accelerating and cornering.
Steve Walker
Azusa, CA
'11 PPV 9C3 Huron White
Arcticolds442
Posts: 25
Joined: Thu Dec 17, 2015 1:30 pm
Location: Middle Tennessee

Re: Slipping shifting into 3rd

Post by Arcticolds442 »

Great info smwalker! Thanks a bunch. And the $$$ isn't much more than a regular trans flush in my driveway, so I am definitely going to try this out.
2012 9C1 DD - stock for now
'72 Olds 4-4-2
'65 AMC Rambler - LQ4/T56 work in progress
"No Bucks Given" '84 VetteKart
'65 Cutlass
Arcticolds442
Posts: 25
Joined: Thu Dec 17, 2015 1:30 pm
Location: Middle Tennessee

Re: Slipping shifting into 3rd

Post by Arcticolds442 »

I just wanted to follow up on this Camaro pan swap for this flair issue. I swapped mine last weekend and it was really easy. The worst part was having to pump new atf into the pan without a fill tube, so I am pretty disappointed in GM for removing it for cost savings. Once on my test drive, the results were obvious. The trans shifted way smoother and best of all...no more flairs before the 2-3 shift under full throttle. None whatsoever.

Thanks again for this great tip!
2012 9C1 DD - stock for now
'72 Olds 4-4-2
'65 AMC Rambler - LQ4/T56 work in progress
"No Bucks Given" '84 VetteKart
'65 Cutlass
smwalker
Administration Staff
Posts: 2201
Joined: Mon Jul 29, 2013 1:44 am
Location: Azusa,CA

Re: Slipping shifting into 3rd

Post by smwalker »

NICE!!! Really glad that worked out for you.

And just notices there seems to be a new number for the ATF fluid and much cheaper on Amazon anyway - AC delco: 10-9395
Steve Walker
Azusa, CA
'11 PPV 9C3 Huron White
User avatar
Raunchtastic
Posts: 113
Joined: Fri Sep 25, 2015 10:53 pm

Re: Slipping shifting into 3rd

Post by Raunchtastic »

I would be curious to see any updates in a few months. I flushed my ATF and had about 3 months of no flares, then they came back sporadically. I would love to get rid of them for good, and may swap the pan just for piece of mind. Who knows, I may just TR6060 swap it so any poor shifts can be blamed on me.
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2012 Chevrolet Caprice "The Daily"
1992 Chevrolet Camaro RS 25th anniversary "The Wannabe Racecar"
User avatar
tedwards0633
Posts: 80
Joined: Thu May 25, 2017 1:48 am
Location: Milwaukee

Re: Slipping shifting into 3rd

Post by tedwards0633 »

I have the same thing happening to mine. I am doing this ASAP.
cerbomark
Posts: 316
Joined: Tue Oct 02, 2018 5:37 pm
Location: upstate NY

Re: Slipping shifting into 3rd

Post by cerbomark »

What I have found when having my fluid /filter changed was that fluid level is critical to proper shifting. This can be difficult without a dipstick but directions for level setting are here on the site. Trans Temp is important when setting.
I have a prefect shifting trans but decided to change filter/fluid anyway. Shop came up short on the re fill (don t know how) but the trans started slipping. Re set fluid level and now back to perfect. I kept everything stock BTW.
2016 C1
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