It is currently Tue May 22, 2018 2:11 am

All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 6 posts ] 
Author Message
PostPosted: Thu Apr 02, 2015 7:28 pm 
Offline
SE Member
SE Member

Joined: Wed Mar 04, 2015 9:23 pm
Posts: 11
Year and Trim: 1984 Buick Century Olympia 3.8SFI Turbo
Hey folks. I have a question and some pictured from an online friend. He has a 1989 Buick Reatta, which has a LN3 3800 and a 440T4 transmission.

The car had been driving nicely, and then one day the transmission started slipping. Owner found massive oil leakage, and topping up the transmission will allow it to drive, but it pours oil.

Upon investigation, he found the transmission case is broken at the final drive end. The end of the case is fully detached, as if it wanted to become a 4T65E with removable final drive cover!

The transmission still moves forward and reverse. The differential function smoothly, you can spin one wheel and the other smoothly spins the other way with car jacked up.

Car has no modifications and the owner is definitely not doing burnouts with it.

Has anyone seen this before? Any ideas what could have caused it?
Thanks,
David

Image

Image

Image

Image


Top
 Profile  
 
PostPosted: Thu Apr 02, 2015 8:04 pm 
Offline
Certified Bonneville Nut
Certified Bonneville Nut
User avatar

Joined: Tue May 27, 2008 8:53 am
Posts: 5300
Location: Las Cruces, NM
Year and Trim: 1993 Buick Park Avenue
1994 Buick Regal Custom
Wow.

I know the 4T60 (which I believe is a tweak of the mentioned unit) supposedly didn't have the best of lubrication in the differential, so when one wheel would spin, it would wear the pin on the pinon gear, and eventually it could start backing out. When it backs out, it essentially starts cutting the casing in half around it, until it cuts all the way through, or gets thin enough that it breaks on its own.

There is no telling the actual cause until the tranny comes out and is taken apart. I also think the transmission will still work until the pin works it's way completely out, at which point power stops going to the wheels and the car drops where it sets, other concerns aside.

_________________
~Randall~
ImageImage

1993 Buick Park Avenue - 197k - Some odds and ends done - Simply won't die
1994 Buick Regal - 78k - Bone stock - Always ready for a good kicking
1990 Oldsmobile 88 - Gone to a better place


Top
 Profile  
 
PostPosted: Thu Apr 02, 2015 10:26 pm 
Offline
Certified Bonneville Nut
Certified Bonneville Nut
User avatar

Joined: Tue Aug 25, 2009 8:32 pm
Posts: 4323
Location: Dearborn, MI
Year and Trim: '93 SSEi
'05 STS-4
'97 Camaro
'97 LeSabre
^^ +1, Roll pin that holds the differential pin in place either fell out, or broke, and allowed the diff pin to slide out and hit the case and wear through until it cracked. Common problem across 440t4, 4t60, and 4t65.

Unfortunately you will need a new case to fix that on the 440t4. I usually flatten the ends of the roll pin so it can't work it's way out when I rebuild the 4t65's.

_________________
I don't know how much boost it takes to blow the tires off. But I know how much I'm going to use!
Image

Runs:
'93 Pontiac Bonneville SSEi - Twincharged, manual, racecar! Build thread
'97 Chevy Camaro - 3800, T5, T-tops, my DD
'05 Cadillac STS - V8, AWD, her DD
'89 Buick LeSabre Limited - winter DD
'84 GMC Sierra Classic - Twin turbo 3800
'97 Buick LeSabre - L67 project
'92 Pontiac Bonneville SSE future project

Doesn't run:
'87 Buick LeSabre T-type - future victim
'67 Buick LeSabre - future victim


Top
 Profile  
 
PostPosted: Fri Apr 03, 2015 7:55 am 
Offline
SE Member
SE Member

Joined: Wed Mar 04, 2015 9:23 pm
Posts: 11
Year and Trim: 1984 Buick Century Olympia 3.8SFI Turbo
Thanks for the insight guys. I will forward this to the car's owner.
Sincerely,
David


Top
 Profile  
 
PostPosted: Fri Apr 03, 2015 11:42 am 
Offline
Administrator
Administrator
User avatar

Joined: Mon May 19, 2008 7:01 pm
Posts: 16691
Location: Central Illinois
Year and Trim: 1992 SSE
2009 G8 GT
I had a diff pin back out. It would make a clicking when I turned from a stop. The rebuilder told me it almost wore through the case and he was amazed it didn't crack.

_________________
Image
WHITE WHINE - IT'S INTOXICATING. 1992 SSE Supercharged 236.26 ci (.040 Over)
15.090 at 90.2 MPH on old engine w/ slipping trans & melted O2 sensor - Gen 3 M62 and matching TB, Gen 2 Pully, Zillamotorsports Ported LIM, YT 1.72 Roller Rockers, SII FPR & Injectors, Easy Performance Gen 3 Air/Fuel Calibrator, Hypertech Thermomaster chip w/ 160 Thermo, TransGo Shift Kit, Infinity/Pioneer Speakers and 10" Subs, 1300 watts, 140 amp Alternator, Ricepipe CAI w/ heatshield, Pilot Angel Eye Foglights, Clear Corners, '02 17" Chrome Bent 5's, Magnaflow F-Body Muffler and Hi-flo Cat, McCoy Motorsports Ceramic Coated Ported Exhaust Manifolds, Fan Override, PowerSlot Slotted Rotors.
2009 G8 GT - Sport Red Metallic, loaded, SOLO Axlebacks, Rotofab Intake, Tuned, autodim Trailblazer mirror, removed intake manifold cover, HSV GTS triple gauge pod, two tone red-hot shifter and HSV SuperSport steering wheel, GXP rear sway bar and diffuser


Top
 Profile  
 
PostPosted: Sun Apr 12, 2015 10:18 am 
Offline
Retired Admin/Techinfo Admin
Retired Admin/Techinfo Admin

Joined: Mon May 19, 2008 2:08 pm
Posts: 26004
Location: Space Coast, or at least it used to be
Year and Trim: 03 SLE, 95 SE, 95 TS SE
Yup, diff pin walked out... sadly it's a solid case and doesn't have separate diff cover..


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 6 posts ] 

All times are UTC - 5 hours [ DST ]


Related topics
 Topics   Author   Replies   Views   Last post 
There are no new unread posts for this topic. Motor/Transmission Swap from 1989 Bonneville LE

nathankinser

3

612

Tue Jan 17, 2017 7:09 pm

jradke61 View the latest post

There are no new unread posts for this topic. 1989 ABS

MattStrike

4

1213

Fri Apr 26, 2013 8:15 am

SSEBonne4evr View the latest post

There are no new unread posts for this topic. 1989 LeSabre LN3 MAF trouble...

turbokinetic

7

1096

Sun Mar 29, 2015 6:55 pm

turbokinetic View the latest post

There are no new unread posts for this topic. 1989 Bonneville SSE engine problems

mbarcher

12

4881

Fri Jul 11, 2008 6:46 pm

mbarcher View the latest post

There are no new unread posts for this topic. Replacing the PCV valve on my 1989? What's the EASY way?

nailbomb3

5

1203

Sun Feb 23, 2014 6:05 pm

pontiacsteve22 View the latest post

 


Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group


phpBB SEO