4L60E rebuild. What did I get myself into...? :P

BC K1500

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if you are reusing clutches then just get a seal kit.... which clutches do not look good please post pics. don't get the sonnax wide band! just get a borg warner HE band and make sure your reverse input drum is flat and not dished, if not replace it.


i would also try get a corvette servo, sonnax boost valve and 3l4 springs

I will try and get a parts list together for the 3/4 clutch pack for you in the next day.
I didn't think it was a good idea to reuse the old clutches, that's why I selected the kit whit clutches and steels.
The 3-4 pack is just totally destroyed. Some clutch plates are completely stripped an bent etc... the picture doesn't do it justice.
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I checked the reverse input drum, its not perfect, but from what I read it's still good.

I was going to ask about the corvette servo, everybody seem to change it out. I'm just curious why is it that much better?

The "Line Pressure Booster Kit" is basically increases line pressure by adding O rings to the piston?

I assume the High RPM (3-4/FWD) Clutch Spring Kit is to replace the completely flat 3-4 springs?

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I updated my shopping list.
bushings
ATP Master Transmission Repair Kit
Band
GM Genuine transmission solenoid
ATP B165 Filter
PIONEER 771003
TransGo 7-2P Corvette servo piston assembly
SONNAX 4L60ELB1
High RPM (3-4/FWD) Clutch Spring Kit

Thank you.
 
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Erik the Awful

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I was going to ask about the corvette servo, everybody seem to change it out. I'm just curious why is it that much better?
The stock 2-3 shift is weak if you're towing. The Corvette servo gives a 35% increase to surface area on the piston, firming the shift up. I put one in my 700R4. I considered Sonnax's "Super Hold" Servo, but someone else said it was too firm and that the Corvette servo was just right.

On the bushings, I got all the bushings, but when I inspected them I think I only ended up replacing two. That's one of those things where if they're good you're better off not replacing them.
 

BC K1500

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Do I have to replace these parts?
The seals don't seem to be user replaceable.
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I cleaned all internal parts whit mineral spirits, except the pump and the valve cover. Probably lost more brain cells in the process than I can afford. o_O
Is it safe to assemble it like that or do I need to de grease the parts whit brake cleaner?
 

df2x4

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Regarding the servos... If you're going to change anything I would just do the Corvette servo, don't go billet. I used billet servos (can't remember which brand) when I had the 60E in my red truck rebuilt and it shifted crazy hard. Like break the tires loose on a WOT 1-2 shift in a V6 truck hard.
 

man-a-fre

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Do I have to replace these parts?
The seals don't seem to be user replaceable.
You must be registered for see images attach


I cleaned all internal parts whit mineral spirits, except the pump and the valve cover. Probably lost more brain cells in the process than I can afford. o_O
Is it safe to assemble it like that or do I need to de grease the parts whit brake cleaner?
They call those molded apply pistons.
 

DeCaff2007

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I'm late to this thread and cannot offer much in the way of rebuilding advice, but I can tell you (the OP) that this is bringing back memories of the BOP TH350 I rebuilt, just to say that I did. It really was NOT that difficult, aside from the "special" tool needed for the reverse drum nonsense.

Oh - one piece of advice I can offer: You asked about a suitable parts cleaning solvent. Non-chlorinated Brake Cleaner. I use it on everything that can't readily go in the parts cleaner.
 
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tayto

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the sonnax boost valve gives more pressure and the o-rings prevent leaks on a worn bore, it's a nice piece. it will help clamp the clutches better in conjunction with the Vette servo. vette servo is good for 95% of builds, don't get caught up in the servo "hype". same with clutch material hype, the stock HE clutches work good. Yes, replaced the molded apply pistons.
 

Erik the Awful

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I thought the "Corvette" servo firmed the 1--2 shift, not the 2--3 shift.
It firms up both, but the weak 2-3 shift is the issue. The 1-2 is just more noticeable.

Do I have to replace these parts?
The seals don't seem to be user replaceable.
That's the servo. I don't think I've heard anyone recommend against replacing it, and it's a fairly inexpensive upgrade.
 

0xDEADBEEF

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That must be why my trans is always chirping second, even at light throttle. I didn't realize it made that much difference.
 
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