4l60e question

[MMLX89]

I just picked up an LS swapped 72 C10 a couple of weeks ago. Current running gear is 5.3l backed by 4l60e trans. On my way to work Friday the trans let go. Started with a whining sound, ended with horrible grinding, clunking, and felt like someone slammed on the brakes. No forward gears currently, but reverse still works.

As I started looking into a replacement, one shop is telling me that until I swap over the rear-end from the same vehicle (2003 SIlverado), that I will continue to go through transmissions. The speed sensor and associated parts won't read things correctly, etc.

This seems a bit far fetched to me, but wanted to get your opinions...

[LockDoc]

Originally Posted by MMLX89

I just picked up an LS swapped 72 C10 a couple of weeks ago. Current running gear is 5.3l backed by 4l60e trans. On my way to work Friday the trans let go. Started with a whining sound, ended with horrible grinding, clunking, and felt like someone slammed on the brakes. No forward gears currently, but reverse still works.

As I started looking into a replacement, one shop is telling me that until I swap over the rear-end from the same vehicle (2003 SIlverado), that I will continue to go through transmissions. The speed sensor and associated parts won't read things correctly, etc.

This seems a bit far fetched to me, but wanted to get your opinions...

I for one think they are full of it. There are a lot of vehicles running around with LS based engine/trans combos that are running the original rear ends.... The settings can be changed in the tune if need be to accommodate for shift points, ratio, tire size, speed, and a multitude of other parameters.

LockDoc

[MMLX89]

I agree with you LockDoc, it was hard for me to believe what he was trying to sell. I think I am just going to source a rebuilt trans and swap it myself.

[Willie Makeit]

before you go any further i think you need to find a new transmission shop

[boostedc10]

LOL, run away from that shop as fast as you can!

[Clyde65]

I have a 4.8/4l60e with a 71 (5lug) rearend and 3.73 gears.

It sounds to me like the trans was abused or not installed correctly. Make sure you check how its been installed, what mounts engine and trans. Pinion angle is important as well.

[clinebarger]

I've heard it all now......

[MMLX89]

So I now have had a couple of shops pointing at the electrical/wiring of the trans as the potential failure. I am going to pull codes tonight to se if there's anything to note, but are there any best practices to follow as far as what sensors are critical to the successful operation of the trans? What I don't want to do is invest the money to rebuild and have it occur again.

[MMLX89]

No transmission related codes were found when I scanned it. Pulling the trans this weekend, but still interested in knowing which sensors are required to ensure if this was an electrical/sensor related issue that it doesn't occur again. Any help is appreciated.

[Tork?]

Could it just be a bad torque converter? On my 99 LS1 it had the symptoms you described when the trans was in limp mode. Not sure if that would throw a code though.

[MMLX89]

It's definitely something mechanical thats broken. I can hear pieces moving/grinding when in reverse. It could be a TC that let go though. I just don't know enough about the sensors required, so wanted to make sure I had that understood when re-installing the new trans and TC.

[solidaxel]

Originally Posted by clinebarger

I've heard it all now......

I am following this one!

[MMLX89]

Ok, so I dropped the truck off last week at a local shop. The rearend had grenaded, so I had them replace ring and pinion. Now the trans will only shift manually, but you can row through the gears. They used a scan tool and everything checked out electrically across sensors, solenoids, etc. There is no signal coming from the ECU in 3-4 though.

I can't quite wrap my brain around the fact that if it shifts manually, how the issue can be mechanical. Anyone with more in depth knowledge that can chime in would be appreciated.

[clinebarger]

Originally Posted by MMLX89

Ok, so I dropped the truck off last week at a local shop. The rearend had grenaded, so I had them replace ring and pinion. Now the trans will only shift manually, but you can row through the gears. They used a scan tool and everything checked out electrically across sensors, solenoids, etc. There is no signal coming from the ECU in 3-4 though.

I can't quite wrap my brain around the fact that if it shifts manually, how the issue can be mechanical. Anyone with more in depth knowledge that can chime in would be appreciated.

With the shifter in D4 or D3, The truck will not move forward, Pulling the shifter into D2 or D1, The truck moves forward & you can shift up through the gears.........Is this correct?

If so, The Forward Input Sprag is wadded up & not holding. It moves forward in D1 & D2 because the Overrun Clutches come "On" so power flow can bypass the Input Sprag, Then when enough road speed is gained you can then bump it into D3 (Overruns are on in D3 Only when the trans is in 3rd gear). It will hold 4th gear without Overruns because the Input Sprag "Overruns" in 4th & the Sprag is not effective.

SFK Sprags are notorious for this, The latest GM Sprag Assemblies use a better a Sprag with double cages & wider "Dogs".

[MMLX89]

Yes, that's exactly what is occuring, great explanation! Could this failure be a result of the rear end failing and locking up? Is the best option to rebuild completely, or just replace the sprag?

Originally Posted by clinebarger

With the shifter in D4 or D3, The truck will not move forward, Pulling the shifter into D2 or D1, The truck moves forward & you can shift up through the gears.........Is this correct?

If so, The Forward Input Sprag is wadded up & not holding. It moves forward in D1 & D2 because the Overrun Clutches come "On" so power flow can bypass the Input Sprag, Then when enough road speed is gained you can then bump it into D3 (Overruns are on in D3 Only when the trans is in 3rd gear). It will hold 4th gear without Overruns because the Input Sprag "Overruns" in 4th & the Sprag is not effective.

SFK Sprags are notorious for this, The latest GM Sprag Assemblies use a better a Sprag with double cages & wider "Dogs".

Posted via Mobile Device

[clinebarger]

If the rear locked down while accelerating. Yeah it could break the Sprag. I would be surprised if it only got the Sprag, It usually takes out the Inner & Outer Races requiring A entire Sprag Assembly. DO NOT use a reconditioned Sprag Assembly from Trans part supplier.....They "Hone" out damaged Races, This decreases torque handling of the Sprag & increases the chance of the "Dogs" flipping over putting you right back in the situation your in now, Buy a New GM Assembly! GM part# 24241477. Amazon.com: ACDelco 24241477 GM Original...
It really depends on the shape of your unit??
If it is in really good shape, Replace the 3-4 Frictions & the 2-4 Band. A few minor performance/durability mods would also be a good idea, If you want details, I can post them.

[65Gregg]

Please do^^^

[MMLX89]

Clinebarger- I can't thank you enough for the guidance here. This description definitely makes sense, and I also confirmed the theory with a transmission builder as well.

I think I've decided to go with geared up transmissions out of Florida for the replacement unit. Re-manufactured vs rebuilt that supports up to 500hp and 2yr warranty for 1200 bucks shipped is tough to beat.

[solidaxel]

Originally Posted by MMLX89

Clinebarger- I can't thank you enough for the guidance here. This description definitely makes sense, and I also confirmed the theory with a transmission builder as well.

I think I've decided to go with geared up transmissions out of Florida for the replacement unit. Re-manufactured vs rebuilt that supports up to 500hp and 2yr warranty for 1200 bucks shipped is tough to beat.

Is that plus a torgue converter?
What about a core?

[clinebarger]

Originally Posted by MMLX89

Clinebarger- I can't thank you enough for the guidance here. This description definitely makes sense, and I also confirmed the theory with a transmission builder as well.

I think I've decided to go with geared up transmissions out of Florida for the replacement unit. Re-manufactured vs rebuilt that supports up to 500hp and 2yr warranty for 1200 bucks shipped is tough to beat.

Good luck, You get what you pay for. My 500hp ready 4L60E is around $2500, I don't see how they can build more than a stock unit for $1200.

Is this the one? It says 300HP http://www.geareduptransmissions.com...2pc-case-93-97 Their just throwing Frictions, Bushings & Electronics at it, No mention of a upgraded Sprag, Or replacing the Sprag at all, Guess it's going to get a used Sunshell? Torrington Bearings? I could go on & on.......

Kevlar Band.....WTF?? Kevlar may be good a stopping bullets, But it SUCKS as a friction material, I have seen a Kevlar Band destroy a Reverse Input Drum in 20,000 miles.....It cannot stop the Drum fast enough, So extreme heat builds on the Drum surface, So hot it caves the drum surface in.
A Stock Borg Warner High Energy Band is good to 500hp (With a fairly smooth 1-2 shift) If you want firmer shifts, I upgrade to a aftermarket High Energy Carbon Band with a heavier Anchor.

Keep in mind, If you do have a failure, Your responsible for Pulling the unit, Crating & Shipping it back to them.....Do this a couple times & whatever money you saved initially will be gone. Not counting the down time while your trans is on (literally) the other side of the country.

Buy from a reputable builder, It will cost more now, But as the saying goes "The Bitterness of Poor Quality remains Long after the Sweetness of Low Price is Forgotten."

Give Dana at Pro-Built a call (He's in Cali), Phoenix in Weatherford TX., And there is me , I can do you a nice job, But I cannot compete with bargain basement prices.

Originally Posted by 65Gregg

Please do^^^

If your trans is in good shape, But you want upgrades.... These parts are pretty easy to install, It may sound like a rebuild but it's not, Your not going to be blowing apart Drums & such.....

Sonnax Performance Pack, Includes......
.490" Boost Valve & Regulator Spring
TCC Regulator Valve (Eliminates PWM apply of the TCC)
HD Primer Spring.
Pinless Forward Accumulator Piston.
Pinless 4th Accumulator Piston & Spring.
Pinless 2nd Accumulator Piston & Spring.
8 Torlen Checkballs...They don't beat up the separator plate like steel balls.
2nd Servo cushion spring
4th Servo return spring
2nd Servo D-Ring seals (Replaces the Scarf cut seals)
2nd Servo release (Calibration) check valve.
Accumulator Valve Spring Shim (DO NOT USE) With a DX Accumulator Bushing code that most truck 4L60E's come with anyway.
Drill 2nd Feed Orifice to .073"-.081" (Not .086"-.093" like the instruction state unless you have a 3200+ stall)
.073" Stock Stall
.076" 2500 Stall
.081" 2800-3000 Stall
Amazon.com: Sonnax Performance Pack: Automotive

Sonnax HD 2-3 Valve, Keeps the Overrun Clutches applied in 1st, 2nd, & 3rd when the shifter in in D3 instead of just 3rd, Protects the Input Sprag when racing/wheeling/stupidity/abuse etc. Amazon.com: Sonnax HD 2-3 Shift Valve: Automotive

Corvette 2nd Servo Piston, Amazon.com: 700R4 4L60E Corvette Servo: Automotive (All Corvette, V8 Camaro/Firebird/GTO have this piston from the factory)

Sonnax 2nd Apply Pin, Allows fine tuning the Band Clearance, .050"-.060" is preferred, http://www.summitracing.com/parts/sox-77787-02k

Inner 2nd Servo Cushion Spring (Use with the Sonnax Cushion Spring), This is used on cars with factory Corvette 2nd Servos, Amazon.com: ACDelco 8681195 GM Original Equipment...

Sonnax Smart Shell, Amazon.com: Sonnax Smart Shell Reaction Shell:...

Wide Sungear Bushing, Amazon.com: Sonnax 77010-01 700R4 WIDE SUN GEAR...

Teflon Lined Rear Stator Bushing, Amazon.com: Sonnax PTFE Rear Stator Support...

Borg Warner/GM High Energy Band, Amazon.com: ACDelco 24232236 GM Original...

Borg Warner 29 Element Forward Input Sprag, Amazon.com: 700R4 4L60E 4L65E Input Forward...

Parts for a 7 Friction 3-4 Clutch Pack......

GM 3-4 Clutch Apply Plate, Amazon.com: ACDelco 8685044 GM Original Equipment...
GM 3-4 Clutch Backing Plate, Amazon.com: ACDelco 24212460 GM Original...
7 Borg Warner/GM .080" 3-4 Frictions, Local Trans Supply House. http://www.makcotransmissionparts.com/74100A.html Not 100% these are genuine Borg Warner.

6 Kolene Treated .077" 3-4 Steels, http://www.makcotransmissionparts.com/74120AK.html




4L60E's only have 2 Clutches that do "work" while in Forward Gears, The 2-4 Band & the 3-4 Clutch, That is why I recommend freshening these two components while doing the above upgrades.

I've spent 50+ hours tweaking this calibration. With quick, crisp shifts that don't break your neck or Parts but still have the pressure rise & clamping power to hold 400 foot pounds. Enjoy!

[BR3W CITY]

MY 80e rebuild was mostly stock with a few upgrades and ran like $1400ish. Add another grand for a convertor.



....speaking of which, I need a new convertor...these things aren't cheap

[foamypirate]

Originally Posted by BR3W CITY

MY 80e rebuild was mostly stock with a few upgrades and ran like $1400ish. Add another grand for a convertor.



....speaking of which, I need a new convertor...these things aren't cheap

I found that out when I was shopping for 80E converters. I ran into some budget constraints and had to get the truck on the road, so I wound up with a $124 Transtar reman. I kind of get the feeling it's a ticking time bomb behind an LQ9 in a 6000 lb 88' R20 crewcab, heh.

[BR3W CITY]

Yea. My current one is like a 2800prm stall, 3disk lockup unit which "supposedly" has an anti-balloon plate for nitrous...tho I have questions about that, since back when I bought it I didn't know what I was looking for.

I need around 3800rpm now, but probably going with billet. For the 80e they are like 8-1500, with a few going higher.

[chev3600]

Clinebarger: thanks for taking the time to put this list together. There are so many opinions out there, it's nice to hear from real world experience.

[65Gregg]

Thanks for your efforts and contributions