Hello everybody. I am looking for some input on a 4L60e rebuild. I have built 2 before so I am definitely still green. I have done plenty of research and now am to the point where I need to narrow down some the requirements for my build. New parts and information are always changing, so I want to make sure I have to most current information.

As for my transmission application; it will be going in a supercharged (M122) LS1 S10 4x4 with 35” tires with target output of 500 wtq. Current transmission is a mish mash of parts and am surprised it is still going.

Current parts:
• 2005 core with ~120k miles
• Sonnax Input Drum Reinforcement
• Sonnax pinless accumulators
• Sonnax 4th billet servo
• Sonnax forward piston
• Beast Sunshell
• B/W 29 forward Sprag
• Transgo separator plate
• Corvette 2nd servo
• OEM 5 pinion planetary set

Parts to order:
• Torrington bearing kit
• Torlon *****/bushing/seal kit
• Sonnax 0.490 valve
• Transgo HD2 shift kit or custom kit if available
• B/W HE 3/4

Questions/Concerns:
- I have read to stay away from the red material and Kevlar bands. Suggestions on 2-4 band, forward, reverse, overrun, low, etc. clutches?
- Standard width 2-4 band or upgrade to the wide band and new drum?
- Will the Beast suffice or would it be a good idea to upgrade to the Smart Shell?
- Recommend a new solenoid and wiring kit?
- I was not planning on the Sonnax HD input drum, hardened shafts or any pump upgrades. Thoughts/should I reconsider?
- Any other comments or suggestions/missing something?

Thanks in advance for the feedback. I am hopefully going to start tearing down the Craigslist special core this weekend.

 

ive never had a problem with the alto wideband(red) the carbon is supposed to be better go with that if possible and get a new ac delco reverse input drum..forward reverse overrun frictions just use any regular clutch don't need anything fancy but for 3/4 your right on with the BW high energy..being 4x4 and supercharged I would get a billet output shaft..input shaft a hardened will do just fine..pump rotor if you can get ahold of a billet one its a awesome upgrade if not look for a oem 10 vane kit with rotor..if you can find a shop near you to ream your pump and install a sonnax oversized pressure regulator valve would be a good upgrade too..drill feed holes too transgo specs except for the 2-3 I go .110 there..the rest of your parts are good while your in there might aswell upgrade the corvette servo to a sonnax 2nd gear..beast sunshell will do fine I have never had one go bad or heard of anything breaking it

 

I have never seen a "Beast" break either, But have seen some with a TON of run-out/bent enough that the Reaction Shaft & 3-4 Clutch Hub wobbles. If yours is straight by all means use it.

Can't use Trans-Go 2nd Accumulator springs with a Pinless Piston, It will likely break springs, Not that Trans-Go doesn't already have "Spring" quality issues to begin with....

 

GMCSIERRA is giving good advice.
You can probably skip the HD2 shift kit and just drill the separator plate as he said, if not already done.
I hadn't heard of an oversized pressure regulator in the pump; I'll have to look that up.

You may want to think about replacing the TCC valve in the VB before you get Code 1870. If you want to keep it PWM, a shop can ream the VB for the Sonnax oversize one. (The value is about $40, but the special reamer is $150; hence find someone that has the tool and experience.)
Else install a TCC On/Off valve such as the one in the Transgo HD2 kit, the Sonnax Perfomance Pack or the Fitzall.

And yes, I would also suggest the Sonnax 2nd gear servo. A wide red or Carbon band is the way to go, but you must then install a new reverse drum.

If you want his suggested billet pump rotor, contact FinishLine Transmissions.

 

And now I see Clinebarger's post, which also makes good points. (As usual.)

 

Thanks for all the input. Sounds like I have to update the parts list:
- I will be getting a wide carbon with a new input drum. Would a wider band also help out with towing?
- I will definitely have to investigate the sonnax oversized pressure regulator. Haven’t even thought of that.
- Sonnax second gear servo

Clinebarger – You mentioned beast bent issue. Is this a manufacturing issue or something that happens while in service? Is there something I can look for to see potential failure? The beast is in the current transmission in the truck and there are no vibration issues.

It is interesting that you say the Trans-go HD2 and the pinless accumulators are incompatible. I didn’t know that during the previous build and that is what I have currently running. A HD2 shift kit with Sonnax pinless… among other things.

What are the benefits of a billet pump rotor over the cast version?

 

If your Beast has no vibration issues, generally noticed in 3rd gear, then it is fine.
Yes, a wider band will help with towing in 4th gear; you already have the 4th gear billet servo.
Absolutely true that with Pinless pistons you cannot use HD2's 1-2 accumulator setup which has a spring on each side of the piston. I have document that several times.
PBA documented how to modify Pinless pistons for the HD2 springs, but that is a lot of effort and might require a lathe. If you really want the very firm shifts of the HD2 setup, you can just use a new stock piston; check your housing for wear. Remember that very firm 1-2 shifts put a lot of strain on the trans and drivetrain.

There are enough reports of pump rotors breaking, that the billet rotor is a high-end upgrade.
Personally I suspect many pump rotor problems are due to ham-handed converter installations. Maybe not the current one, but a previous one may have caused a small crack.

 

I believe it is a manufacturing/handling/packaging/ issue, Back when I did use Beast Shells, I would order 3 of them, And hope 1 would be straight, Sometimes all would be good, Other times all were trash. Comes with the territory with off shore manufacturing with little to no quality control, Then shipped half way around the planet.

Never seen one go bad in service though. If you have a good one, Use it!

You haven't opened up the 2nd Accumulator Housing yet...

 

Ok cool. I will stick with the beast. Thanks for the feedback. I will have to see what the 2nd accumulator looks like when I pull it apart...

Mrvedit – You mentioned earlier to forgo the HD2 kit all together for the pinless and VB TCC valve. Are there any other recommendations to the VB I could do?

Also, what would you recommendations be for the 3-4 clutch stack in the stock drum using BW? And what steels to use? Thanks for all the help.

 

I recommend the Sonnax 2-3 HD shift valve which requires a small mod to the VB.
With this mod you can race in D3 and the overrun clutches will stay engaged in all gears which reduces the load on the forward sprag.

For the 3/4 clutch use BW HE or Raybestos GPZ frictions. 7 .080 frictions, 6 .077 steels and the thickest (new!) apply and backing plates.
(I'm on vacation and cannot easily access other threads, but Clinebarger has documented all the part numbers.)

And perhaps Clinebarger can also document other mods in lieu of a full shift kit.

 

Thanks for the feedback. Did you mean 0.76 steels with the 0.080 frictions?

I will look into getting the updated Sonnax VB parts. Now I just need to find a shop that can do the VB reaming...

 

Yes, sorry, I was on vacation and didn't have access to all my notes.
I corrected my post above.

Clinebarger's recommendation in another thread is good:
=====================================
I recommend a Borg Warner Friction Module (with 6 .080" 3-4 frictions) 34036KIT is the Borg Warner number, Buy 1 extra BorgWarner .080" 3-4 friction for a total of 7.
6 .077" 3-4 Steels.
3-4 Apply Plate GM# 8685044
3-4 Backing Plate GM# 24212460.
=====================================

Don't try to save a buck by reusing the apply and backing plates as they bend over time and old ones are more likely to cone/ruin your new clutch.