Originally Posted By: NDL
Originally Posted By: clinebarger
Sounds like a leak in the Input Clutch circuit, It will cause the EXACT symptoms you describe!
There are 3 areas of concern in the Input Clutch circuit.....
1. The Input Clutch Apply Piston inner sealing area gets worn & the Inner Lip Seal can no longer effectively seal against the piston.
2. GM used a "Short Lip" inner seal, This is an extension of #1.....The short Lip allows NO compensation for the Piston wearing.
3. Leaking-Shrunk teflon sealing rings on the Input Clutch Housing.
A combination of #1 & #2 is the usual culprit, Repairing this requires removal of the trans & partial tear down, The piston can most likely be saved by polishing the sealing surface with some fine emroy cloth. Replace the short lip inner seal with a Long Lip design that was factory in TH440-T4/4T60 units. Most aftermarket 4T65E seal kits come with the early long lip design seal.
The Input Clutch & Piston are worked to death in this unit, It is "On" in 1st & 2nd gears & "off" in 3rd & 4th gears.
I don't have any input about "seal conditioners" or other additives to band-aid this well documented issue. Good Luck!
I am not being lazy by asking; I did a search, and couldn't find information that the average person would/could understand:
I am reasonably new to Charlotte; it's times like this that stink, because I don't know who's what (which shops are good, and which to avoid). Even the better shops will have a customer gripe from time to time online...
All of that said: is what you described a major job? Is it a major teardown of the transmission? Got any ideas on what a repair might cost?
Thanks in advance
Trans-Go prints tech information about this issue right on their Shift Kit directions.
In GM's eye's....A worn Input Clutch Apply Piston at 120,000 miles is normal wear, The Zombie's at the plant were cutting/rolling the long style Lip Seals, The short style was implemented only to aid in assembly.
I've been out of the general transmission service Industry for awhile now & specialize in performance transmission builds, That includes a few 4T65E-HD units from supercharged V6's & LS4 V8's.
I would charge you the book time to R&R the unit, Plus 4 hours for tear-down, Inspection, & repair of the Input Clutch Cicuit, Filter & ATF......IF you really insisted on patching the unit.
6.8hrs to R&R X $85.00 = $578.00
4.0hrs to D&R X $85.00 = $340.00
1.0hrs to install Trans-Go shift kit = $85.00
Cost + 10% on the ATF, Filter & Shift Kit.
I would install new Solenoids & converter for free if the customer supplies them.
Originally Posted By: clinebarger
Sounds like a leak in the Input Clutch circuit, It will cause the EXACT symptoms you describe!
There are 3 areas of concern in the Input Clutch circuit.....
1. The Input Clutch Apply Piston inner sealing area gets worn & the Inner Lip Seal can no longer effectively seal against the piston.
2. GM used a "Short Lip" inner seal, This is an extension of #1.....The short Lip allows NO compensation for the Piston wearing.
3. Leaking-Shrunk teflon sealing rings on the Input Clutch Housing.
A combination of #1 & #2 is the usual culprit, Repairing this requires removal of the trans & partial tear down, The piston can most likely be saved by polishing the sealing surface with some fine emroy cloth. Replace the short lip inner seal with a Long Lip design that was factory in TH440-T4/4T60 units. Most aftermarket 4T65E seal kits come with the early long lip design seal.
The Input Clutch & Piston are worked to death in this unit, It is "On" in 1st & 2nd gears & "off" in 3rd & 4th gears.
I don't have any input about "seal conditioners" or other additives to band-aid this well documented issue. Good Luck!
I am not being lazy by asking; I did a search, and couldn't find information that the average person would/could understand:
I am reasonably new to Charlotte; it's times like this that stink, because I don't know who's what (which shops are good, and which to avoid). Even the better shops will have a customer gripe from time to time online...
All of that said: is what you described a major job? Is it a major teardown of the transmission? Got any ideas on what a repair might cost?
Thanks in advance
Trans-Go prints tech information about this issue right on their Shift Kit directions.
In GM's eye's....A worn Input Clutch Apply Piston at 120,000 miles is normal wear, The Zombie's at the plant were cutting/rolling the long style Lip Seals, The short style was implemented only to aid in assembly.
I've been out of the general transmission service Industry for awhile now & specialize in performance transmission builds, That includes a few 4T65E-HD units from supercharged V6's & LS4 V8's.
I would charge you the book time to R&R the unit, Plus 4 hours for tear-down, Inspection, & repair of the Input Clutch Cicuit, Filter & ATF......IF you really insisted on patching the unit.
6.8hrs to R&R X $85.00 = $578.00
4.0hrs to D&R X $85.00 = $340.00
1.0hrs to install Trans-Go shift kit = $85.00
Cost + 10% on the ATF, Filter & Shift Kit.
I would install new Solenoids & converter for free if the customer supplies them.
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