4L80E build

Joined
Feb 24, 2019
Messages
1,495
Location
Not here
So like many my rebuild project started off to be a pretty much stock rebuild and after a lot of research it is steadily growing in scope. The original plan has been to replace all electrics, Rekit it with BW high energy frictions and bands, stock steels, bonded pistons, all bushings and sprags, rollerize the rear and install an HD2 VB kit. I took the transmission bench class and am doing disassembly and parts inspection according to the McCormick rebuild manual.
This trans is going behind a Texas speed prepped Salvage yard 6.0 LQ. The motor and trans will be controlled by a Fitech "Retro" stand alone. Both will be installed in a 4100 lb cruzer Porterbuilt slammed P-10.
The goal is to end up with a tough 80E that don't knock my coffee off the console when it shifts and be drivable.
TSP recommends a 3000 rpm converter. Their best guess is 500-600 hp with the cam they specified.
Major disassembly is complete, the case have been steam cleaned ,closely inspected and 2 coats of ppg gm1 silver lg. As per the McCormick book sub assemblies disassembly has started from the front parts going deeper in from there.
 
The TransGo HD-2 kit is an absolute waste of money when your rebuilding the unit!!! It's designed to Dual Feed the Directs without disassembly with the use of a triple layered Separator Plate......This plate can cause crossleak issues & sticky valves in the Valve Body!!
Don't get me wrong, For a guy that buys a "yard" 4L80E & wants more power handling without internally Dual Feeding.....It's not a bad alternative!!

If you have already bought the kit......The Intermediate Clutch Snap Ring & High Rate Direct Return Springs are good pieces, But I would buy a TransGo 48-PLT-01 replacement plate & Internally Dual Feed!!!!!
DO NOT use the pressure Pop-Off parts in the kit!

If you need any technical assistance....Just ask.
 
Front pump was opened up and gears look ok with nothing obvious. Pump will be further disassembled later. Disassembly and inspection of the turbine shaft and overdrive assembly show the following. Inboard end of the turbine shaft shows definitely signs of wear at the seal ring area. Planetary was locked to the spag and had to use a puller to separate. All of the frictions and plates were welded together and snap ring had been so hot it warped and was partially out of its groove. The thrust bearing in the overdrive drum is rough. There is also notable wear on the outside of the overdrive drum from the 4th clutch frictions.
Question 1 since obviously I will be replacing the turbine shaft, planetary and overdrive drum, can I upgrade these parts to a later year to get the tougher sprag assembly and still reuse the 2000 4th drum?
 
Looks like we are both typing at the same time. Pecking for me.
I have not bought any parts yet. And this unit came to me with the sandwiched kit stamped transgo 48
 
The 2001 & up units actually use a smaller Overdrive/Overrun Roller Clutch than the 2000 & down units. The 4th Clutch Housing can be used with either design Overrun Clutch Housing & Overdrive Planetary Carrier. However......The Overrun Clutch Housing & Overdrive Planetary Carrier MUST be used as a matched set.

I've had better luck with the early design OD/OR Roller Clutch, But you should avoid dogging it with the shifter in D4, Put in it D3 so the Overrun friction come on & help support the Roller Clutch.
Sonnax has a kit that keeps the Overruns applied during 1st, 2nd, & 3rd with the shifter in D4, And releases the OR's upon the 3-4 upshift. Seems fine in a work truck.....But feel/felt a slight bind on the 3-4 upshift in a high performance trans I tried it on. Amazing what you can feel in a light car compared to a 7,000 pound truck.
 
Originally Posted by P10crew
Looks like we are both typing at the same time. Pecking for me.
I have not bought any parts yet. And this unit came to me with the sandwiched kit stamped transgo 48


Like I can type......I invented the "Hunt & Peck" technique
grin.gif
 
So if I understand correctly I should just get the 2000 parts? I know exactly what you mean with regards to the shift feel in a heavy rig versus light. My kitted 700r4 tow rig annoys the [censored] out of me on 1-2 shifts when I don't have anything on the trailer but when loaded it's perfect.
 
Originally Posted by P10crew
So if I understand correctly I should just get the 2000 parts?


That is correct.

Have you checked out the Forward Drum where the Turbine/Input Shaft sealing rings interface? Worn bushings/Overdrive component failures are known to cause wear in this area.
WIT & Transtar sell reconditioned Forward Drums that have been sleeved.
 
Well when I get pics from my phone they are rotated and I can't rotate them after posting. I should be able to drop them upright on the next ones.

No I have not inspected the forward drum/ input interface yet. Just assuming that is toast too.

What parts do you ALWAYS replace in the pump?
 
Overrun Frictions burning down like that is a telltale sign of a Crossleak. Rarely do the Overruns distress much less burn-up!

The 4th Clutch & Overrun Clutch should never be "ON" at the same time!
 
Originally Posted by P10crew


What parts do you ALWAYS replace in the pump?


Pump Bushing, Front Seal, Both Stator Support Bushings, Boost Valve assembly, Pressure Regulator Spring, Drill out the drain back circuit, Drill a Lube To Line Bypass.
*If the Pressure Regulator bore plug is loose.....Sonnax has a plug with a O-ring.
*The Pump Body, Pump Cover, & Pump Gears need inspection & culled if worn/damaged.

On a High Performance unit....I recommend replacing the pump gears with PTFE/Teflon coated gears from CK Performance.
 
The filter to case grommet was hard as a rock and loose in the case and on the filter so I would also assume that it was pulling a lot of foam

Further disassembly, inspection and questions coming tomorrow. Thank you!
 
What do I need to specify for the boost valve and regulator spring? My main goal at first here is to get all parts inspected and make a hard parts list as I go deeper. Then once all stock hard parts have been inspected I would like to make the list of upgrade parts needed,reamer kit and any drill bits that are not in the kit. I have letter, number and fractional sets
With the transgo separator plate kit is there going to be any drilling of the case?
I'll post up findings tomorrow. Thanks
 
Cline where's the best place to start a shopping cart for the kit, hard parts, transgo and sonnax parts?
 
Originally Posted by P10crew
Cline where's the best place to start a shopping cart for the kit, hard parts, transgo and sonnax parts?


I use Whatever It Takes(WIT) & Transtar Industries.
 
Back
Top