Tranny or Diff ? Need help testing
Thread Starter
Drifting
Joined: Apr 2002
Posts: 1,720
Likes: 19
From: Manhattan Beach Ca
Tranny or Diff ? Need help testing
One day after I replaced my differential support bracket nut that had fallen off, I now have some kind of major failure in the drivetrain.
As I was driving I could hear a dry metallic spining sound but couldnt figure out from where. Then the car basically gave up on me by not going into gear so I pulled over 2 blocks from home. I put in reverse which worked fine. Then into first which seemed to barely work and just kept it in first all the way to my garage.
Got it up on blocks for inspection but saw nothing from the outside/underside. Started engine and ran through gears with wheels hanging and spinning and all gears seemed to work fine. So problem is while under load which I havent tried to repeat yet.
Thats why I am asking now for ideas on how to tell or test if tranny or diff is the culprit? All ideas appreciated.
As I was driving I could hear a dry metallic spining sound but couldnt figure out from where. Then the car basically gave up on me by not going into gear so I pulled over 2 blocks from home. I put in reverse which worked fine. Then into first which seemed to barely work and just kept it in first all the way to my garage.
Got it up on blocks for inspection but saw nothing from the outside/underside. Started engine and ran through gears with wheels hanging and spinning and all gears seemed to work fine. So problem is while under load which I havent tried to repeat yet.
Thats why I am asking now for ideas on how to tell or test if tranny or diff is the culprit? All ideas appreciated.
Thread Starter
Drifting
Joined: Apr 2002
Posts: 1,720
Likes: 19
From: Manhattan Beach Ca
Its a 4 speed Muncie with rebuild maybe 10K ago.
Plan to check both fluid tonight and see if one is dry.
I will set down off blocks and try and go back and forth in driveway and see if I can isolate problem.
Plan to check both fluid tonight and see if one is dry.
I will set down off blocks and try and go back and forth in driveway and see if I can isolate problem.
Melting Slicks
Joined: Apr 2009
Posts: 2,632
Likes: 112
From: Great Plains Iowa
Ah, so it IS a manual transmission. When you said it barely moved in 1st gear were you saying the engine was revving but you were hardly moving? If so that would indicate a slipping clutch. Make sure your clutch pedal has at least an inch of free play before it gets stiff. If it doesn't have any free play it could slip something awful; especially in the higher gears.
Thread Starter
Drifting
Joined: Apr 2002
Posts: 1,720
Likes: 19
From: Manhattan Beach Ca
So diff fluid looked fine and full.
Tranny fluid magnet plug had glob of puddy like hardened oil with metal flakes mixed in so not too good there. Tranny fluid level was not to the hole but maybe 1.5 inch below hole which is definitely a bit low.
So wasn't able to check back and forth yet. Try tomorrow.
Tranny fluid magnet plug had glob of puddy like hardened oil with metal flakes mixed in so not too good there. Tranny fluid level was not to the hole but maybe 1.5 inch below hole which is definitely a bit low.
So wasn't able to check back and forth yet. Try tomorrow.
Melting Slicks
Joined: Mar 2008
Posts: 2,989
Likes: 198
From: Meriden CT
Surfer, the oil went somewhere, do you see any evidence it went out the front seal and maybe oiled the clutch down?
Last edited by SH-60B; Nov 18, 2015 at 04:42 AM.
Race Director
Joined: May 2006
Posts: 18,665
Likes: 2,564
You are the same person I told about the bushing problem. You only installed a nut with no bushing and no washer. Are you sure the nose of the differential isn't moving due to the missing bushing?
Last edited by MelWff; Nov 18, 2015 at 01:25 PM.
Thread Starter
Drifting
Joined: Apr 2002
Posts: 1,720
Likes: 19
From: Manhattan Beach Ca
The big doughnut rubber bushing is still sandwhiched between the bracket and frame. I only had to improvise the outer rubber bushing or washer which actually now I'm not even sure what purpose it had.
In either case I see the bracket not going anywhere and shouldnt be a problem now. When it was loose it might have caused the damage I am seeing. Still not sure yet.
In either case I see the bracket not going anywhere and shouldnt be a problem now. When it was loose it might have caused the damage I am seeing. Still not sure yet.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
Thread Starter
Drifting
Joined: Apr 2002
Posts: 1,720
Likes: 19
From: Manhattan Beach Ca
Filled tranny up and only used half a bottle of fluid so not as bad as I thought. Drove back and forth in reverse and first in my driveway with no issues. Guess I need to go back on the street and try and duplicate now.
Thread Starter
Drifting
Joined: Apr 2002
Posts: 1,720
Likes: 19
From: Manhattan Beach Ca
Took test drive and immediately noticed dry rotational sound with spotty shifter issues.
So got tranny on the ground in less than 3 hours which is pretty good for me. Sure enough first thing was a little sleeve was still attached to input shaft of tranny. I'm like whats that? It was part of the TO bearing which had disinagrated into 3 seperate pieces.
This actually upsets me since I went out of my way to buy super HD TO bearing and this thing was no better than regular stock.
So could use some advice on really good TO brgs that last. THX
Good news is only TO brg instead of $1200 tranny rebuild.
So got tranny on the ground in less than 3 hours which is pretty good for me. Sure enough first thing was a little sleeve was still attached to input shaft of tranny. I'm like whats that? It was part of the TO bearing which had disinagrated into 3 seperate pieces.
This actually upsets me since I went out of my way to buy super HD TO bearing and this thing was no better than regular stock.
So could use some advice on really good TO brgs that last. THX
Good news is only TO brg instead of $1200 tranny rebuild.
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
Even a HD bearing will go if the clutch isn't set up correctly or if you ride the clutch. Stopping at lights and holding down the clutch the whole time is the worst thing you can do. The second worst thing is not having enough free play. That's that inch of movement before the pedal starts to disengage the clutch. Without that, the bearing just keeps spinning and burns up in 5000 miles. Simple NAPA parts hold up well for the price.