i've been reading thread after thread on what clutches to use/not to use, and now I'm totally lost.

everyone says to build a trans with 'x' clutch, but dont use it in the 3-4 pack. (referring to alto reds)

my question is, why does it matter?
my 4l70e went 120k miles before i had issues slipping. this was in a trailblazer ss, and it was from abuse.

ive read multiple threads where people have frequent rebuilds from loosing the 3-4 clutch pack, and most of them complain that is the clutch itself? ive read the stickys, and read the most common issues that burn up the 3-4.

why cant i just put OEM clutches back in it and expect another 120k miles??
its a stock TB after all...

whats so 'special' about the 3-4 pack where it needs a 'special' clutch to just get me down the freeway reliably? im not going to drag race in OD, or have WOT upshifts into OD or WOT kickdowns from OD

im not building a drag truck here. i just want a reliable trans that can handle a stock LS2.

 

nobody?

 

Stock Borg Warner frictions are fine, I personally don't like Alto Red's at all in anything.

The only modification I would make to the 3-4 clutch is to ditch the .067" 3-4 frictions in favor of .080" frictions......
7 Borg Warner .080" High Energy Frictions.
6 .077" Steels.
3-4 Apply Plate GM# 8685044.
3-4 Backing Plate GM# 24212460.

Vette 2nd servo (GM# 8642093 & 8642115)

Separator Plate GM# 24244053. Matches the 093 servo.

Sonnax .490" Boost Valve Sonnax# 4L60E-LB2......Good line pressure rise is a must!!

 

the trans i have comes factory with a vette servo. i had a tci rebuild kit at one point and they provided a vette servo as well. I replaced the original with it. But i never got a new separator plate with it. but i did however, drill holes in my original separator plate as the directions specified. i did install the sonnax boost valve, and drilled the bleed orifice larger.

 

The Trailblazer SS/4L70E did not come with a vette servo from the factory, Though the 24229159 was only slightly smaller than a vette servo.

I was assuming this was a stock unit.

 

Whose instructions are you using here? Do not drill the little feed hole on the boost valve. I only used for the last 22 years the Borg Warner Hi-Energy clutches, but I like 8 or 9 in most clutch setups. Corvette servo at a minimum. I use the TransGo .500" boost valve and the Sonnax .490" boost valve is good too, whatever your preference is. Set the 3-4 clutch clearance to .020" - .035" when using the Corvette servo, and the 2-3 feed hole on the separator plate should be .110". This will help increase 3-4 clutch life and make a quicker 2-3 shift at WOT.

 

i had bought a TCI overhaul kit. i did install the corvette servo.

the instructions said that it was an option to drill a larger hole in the boost valve. (i forget the technical name of the hole i enlarged)

ive been told that any 4l60e that came behind a LS engine, came factory with a vette servo. regardless, i have one in it now.

 

also. long story short. i rebuilt the trans once, drove it, and im pretty sure i hurt it? had a lot of gold and clutch in the pan. even after changing the fluid and filter. now its back out, and im trying to figure out whats gone wrong.

 

That gold is brass shavings. One part I can think of that they come from would be the bushings.

 

I prefer Borg Warner Hi-Energy Clutches and have had really good luck with them. The Altos just don't last in my trans. I also use the Sonnax Smart-Tech Housing kit with BW H-E 8-Clutch Setup and use the thickest Frictions/Steels I can to maintain proper clearances.

 

i know for a fact it bushing. but im not sure why im eating up bushings.

 

SKF forward sprags have brass races, Take the sprag assembly apart & inspect the races for damage, Also check the Overrun hub for wear.

Check the rear Stator Support bushing.....This is the only bushing in a 60E I have seen get completely wiped out, Sonnax has a PTFE bushing for this location.

 

I have to question the reasoning behind people spending so much money on a 4L60E, $400 input drum, $400 in 5-pinion carriers, $400 output shaft, $170 billet pump rotor.....so on & so forth.
Save for a C5 Vette.....A 4L80E will fit in place of a 4L60E in most cases.

 

I have $2,800 in my trans, that includes the brand new GM Crate 4x4 4L70E. I never paid close to the prices you listed for those parts. For the Sonnax Smart-Tech Input housing kit which includes the 300mm Billet input shaft, the Billet output shaft and the SmartShell, I paid $700. These parts were brand new, I just know a few people and got them at cost.

I didn't have time to re-pin the harness, mod the crossmember, get new driveshafts. My trans is holding up to 360 rwhp and towing 7,800 lbs every 2 weeks for the last year and a half.

 

That is way below cost for those parts. Most dealers wouldn't have access to that kind of pricing.

 

Says who? What I always tell people is "It is not always about what you know, but about who you know". You would be surprised what cost is on those parts. I purchased those items at SEMA here in Vegas last year, my buddy works there and was able to get me in with a 3-Day pass. They had complete transmissions built by them I could of picked up for a great price as well, though I didn't need at that time. I picked up my Rancho 4" lift kit from Sema the year before for $1200. Retail was $1,460 at Rock Auto, plus I still got to send in the $300 Rebate Rancho has every year. Even if I didnt get them at Sema, I know a two brothers who own a Speed Shop here in Vegas that could of ordered the Sonnax parts at a big discount.

You do not have to believe me, I was just stating that I did not have a ton a money invested in my trans and if it wasn't for getting a steal on the 4L70E, I might of had to swap in a 4L80E or temporarily used a stock trans from a junkyard to get me going in my daily driver. Now the Sonnax SmartTech Input Housing with thicker 8-Frictions is the most ideal setup using the BW H.E. frictions. I used those in my stock input housing as well and it held up great. I never had luck with using Alto's and fried them twice before switching over. I prefer the Borg Warner over the Alto's and the Z-Pack.

-Retail of the SmartShell #77749-02k online is $76.79 from RockAuto
-Retail of the Billet 4x4 Output Shaft #74678S-HD online is $475
-Retail of the SmartTech Input Housing Kit with Billet 300mm Reluctor-Style Input Shaft #77733-12K is $658 but have found for $609 new on Fleabay.

These were brand new items in sealed Sonnax Boxes. I saved around $470, with retail pricing of $1200.
-74678S-HD $280 - Saved 40% off retail
-77749-02K $47 - Saved 40% off retail
-77733-12K $425 - Saved 35% off retail
So a total of $750, $50 more than I thought.

I also picked up a brand new crate 4x4 4L70E (#19260961) from the dealership for $1600 OTD (Retail at the Dealer was $2600 OTD but can be found for $2,250-2,300 online). Someone special ordered the trans and placed a $1,000 deposit on it. The trans has been sitting at the warehouse for almost 30 days before they attempted to contact the guy to come pay off the balance and pick it up. When they finally contacted the guy he said he did not want it anymore and the deposit was non-refundable. My buddy, who worked at the dealership when I worked there, sold it to me for what the guy owed them. Which was $1,480 + Tax.

So between the 4L70E and the Sonnax parts listed above, I am at $2,350.
I salvaged my Complete Pump and inspected it, as well as my Mag-Hytec Deep Pan, some other Sonnax goodies, and Transgo stuff that I could off my grenaded 4L60E. My 4L60E already had a built pump. It had a Billet Pump Rotor, Sonnax Line Pressure Boost Kit #4L60E-LB2, Sonnax HD Pump Slide Spring #77722-01K, Sonnax Stator Support Shaft Assembly kit with Wide Bushings #77918S-09K (I did have to replace the rear bushing), Sonnax TCC Apply Valve Kit #77805E-K, The internal wiring harness which had new Solenoids and the Sonnax TCC Aluminum Solenoid Snout kit with Anti-Drainback Valve #77942-02K.

Other than flow calibration mods internally which differs from transmission builder to another, I would say my transmission is built up to par with those of the top builders who charge $4-5000 transmissions and for half the price. If I had to put any more money into it or it blows up tomorrow, I will swap in a 4L80E without a doubt. I know the 4L60/65/70/75E transmissions are not the stoutest, even though the 4L75E is rated at 650 lb-ft of torque, but it will do for now.

 

what would make me destroy a bushing on a new trans?

 

I'm not calling you a liar, The shop I work for is a Sonnax dealer.....Though not the highest tier because We don't buy or push many of their high end products. Some of their 4L60E stuff is silly. For example
Billet Input Shaft, Since when is this needed?
Aluminum TCC Snout, The factory one is very reliable.

The Smart Tech Drum being the "Most Ideal" is debatable as it does not add enough durability to offset the cost in my opinion.
The video of the backing plate bowing is pure propaganda, They are not using the latest backing plate like the one I gave a part number for. They are probably testing a thin aftermarket plate.
Snap Ring blowout is caused by the backing plate bowing.
Internal friction drive tangs are still susceptible to wear off/strip out in a high mileage unit.
The Apply Piston is still to small.
People get too caught up with friction count, When Clamping Force is far more important.


Sounds like you built a good unit, I hope it lasts. I understand it being 4wd would have cost more than a 2wd to swap in a 80E, And you got a hell of a deal on your parts. For you it made since (though I wouldn't have thrown the sonnax kitchen sink at it). For a lot of people on this board....Not so much.

 

Which bushing got destroyed? Could have been an installation error &/or a Lubrication issue.

 

I am no expert on the new electronically controlled transmissions. I have dealt with and built many of the older PG/TH350/400 in the past. With these newer electronically controlled transmissions, I have learned most of my knowledge by taking one apart and seeing how it works. So there is a lot I do not know, such as altering the fluid pressures at any given RPM using a laptop, instead of changing springs/adding washer or messing with the regulator. You seem to know a lot more than I do so please excuse some of my "Noobness" to this.

Only reason I went with the billet input shaft was because it came in with the input housing, now I know I could of just got the housing but it was not much difference in price. Better to have than not I guess lol. I have broke a Solenoid Snout during disassembly and also found a broken one in a junkyard trans before, I thought it was a nice little piece, but is not needed.

I said the SmartTech Drum with 8 frictions (Over 9) is the most ideal, not just the drum itself. Most transmissions shops I have talked to think the Sonnax SmartTech Drum is the best thing since sliced bread, that may be the reason I went with it. I honestly do not know what is best, just went with it since it was recommended. I agree, clamping force is way more important than the plates themselves. You can have 100 plates and if they do not have enough pressure, they will still slip.

We will see how she holds up. I did every mod to it myself, including drilling and modding the pump, separator plate and Valve body for better flow and better pressures. Kinda nerve racking when you only know mostly what you are doing lol. I just had another tune done and lowered the shift pressures at idle to 1/4 throttle. Shifts were way to hard at low rpm, which is now fixed.