Took a video of how loose the diff was before I pulled it off and seen how broken it was
I think I hurt it while I was autocrossing it two weeks ago. I noticed on the way home that it was whining on decel only. It drove fine otherwise so I took it to detroit for a Wbody/3800 car meet. Cars from all over the country showed up. It was a huge turn out. My Fiero and my friends turbo 3800 blazer were the only two 3800 swapped cars there. I did several WOT pulls and it seemed fine. Late that night whenever I would make left turns under load it felt like the rear end would lock up for a split second. It felt like metal was getting in the gears. Then It started to feel really sloppy between accel and decel so I decided to make a beeline home. Still shifted fine and the whining on decel was louder. I went about 300 miles since the autocross. Pulled it apart tonight and I was surprised it still drove as good as it did. I'm sort of kicking myself in the butt for continue to drive it while I knew it was hurt. I might have been able to just toss in the other diff from the first F23 I messed up.
When I was autocrossing I would leave it in second gear and never touch the clutch. I think the constant high load and high load decel at 4,000-6,000 rpm was really shock loading it. The course isn't usually set up like that but it was just about perfect for my car with the trail braking and probably why I did so well.
A little video of me at the autocross doing bad. I did get 2nd overall fastest time for the day.
Love that your F23 has taken the torque. I want to use a Vue version behind a stock(ish) 2.8 for road racing. I'll definitely be looking you up when I have parts ready to go!
It's very gracious of you to torture test this transmission for the community. Thanks!
The driver's side is right next to the ring gear and sees all the radial loading from the final drive mesh. It's not surprising it broke that way.
The passenger side diff bearing takes the axial load from the helix angle of the final drive mesh. When that load is too high, the case splits and the bearing boss departs. 282's frequently fail this way BUT the F23 has a MUCH more robust case in that area.
You still running the 3.63 gears?
The whining was probably from the chipped tooth on the pinion.
I picked up another FY1 F23 yesterday for $250 and got it all bolted up. I found a crack in a rear rotor so i'm waiting for new ones to come in before I put the brakes back together.
quote
Originally posted by Will:
You still running the 3.63 gears?
The whining was probably from the chipped tooth on the pinion.
Quaife?
Still 3.63.
If this same failure happens again i'll have to address it. Do you think the Quaife would be a stronger option?
Your symptoms were the same as mine in the F40 failure, occasional binding from metal getting between the gears and crunched, and severe whining on decel. The whining is from the poor gear meshing due to increased tolerances the same as in a rear wheel drive differential that is not setup properly. In my case a 3 rd gear acceleration is where the failure started resulting in excess clearance between the gears on and off depending the position of the bushing that was moving out of place as a result of the synchro ring failure, the synchro parts are what chipped the gears.
Look up the GM spec sheet on the F23 and find out which gears have the highest torque ratings, In the F40 I recall it being 2 nd and 4 th gear hence the 3 rd gear trouble spot although 2 nd experienced far more high torque cycles.
Bump! How is the F23 holding up now? I'm looking to do the F23 FY1 too on my modified 3800SC. Do the gears seem short at all or is a high HP motor and the F23 "economy" gearing a good match for a mixture of drag strip and street?
------------------ ------------------------------------------------------------------------------ My pics and videos: www.corvettefan86.com -1986 GT -Swapped 2001 GTP motor Series II with 40k miles -2.8 Pulley, Ported Supercharger, Stage III Heads, Full-Stack ZZP Intercooler, ZZP XPZ Cam, True cold air intake, 3" inlet, North* throttle body, 40# Injectors, Flowmaster 80 series, 2 1/2 Mandrel exhaust
[This message has been edited by CorvetteFan86 (edited 10-28-2014).]
I love the gearing. I think it's perfect especially with the big turbo cam I have. Car has been down for 2 months now. I've been busy and still working on getting a twin disk in it.
For those of you that have split the cases on the F23 to change bellhousings or change out differentials, where are you finding the plastic plugs to cover the gear shaft that must come out to split the case? All the part numbers I have come across are showing as no longer available.
For those of you that have split the cases on the F23 to change bellhousings or change out differentials, where are you finding the plastic plugs to cover the gear shaft that must come out to split the case? All the part numbers I have come across are showing as no longer available.
According to others on this forum the correct OE part numbers are: 9120609 and 9120610. I've confirmed them via the excellent cataloging posted on http://www.wholesalegmpartsonline.com/ . The parts seem to be available at most of the online GM parts vendors.
Wahoo!!! My first posting since registering maybe 10 years ago. Hope it helps!
Do you have pics of the mounting locations for the front and rear trans brackets? I need to show them to Roger Thelin to see if his brackets will work with the 2.2 pushrod bellhousing. Thanks!
There are different case locations depending on the case. The 2.2 pushrod bellhousing is missing at least one of the front bracket mount locations that Thelin's Ecotec F23 bracket uses.
