4L60E Shifting issues?

[SiriusC1024]

That's good info on why the 60 is a heap of garbage. TLDR: Get a 4L80E.

Still, you're trying to shift WOT above GM rated RPM. What do you expect? I tried to explain. Look it up it's all over the internet. 6000rpm. There's probably some type of wear from shifting above rated previously.

https://cpt4l60e.com/what-rpm-should-a-4l60e-shift-at/

"Stock 4l60e / 4l65e transmissions shouldn't be shifted at more than 6,000 RPMS. Can it be shifted higher? Yes, but this will quickly cause the longevity of the transmission to suffer and ultimately fail. Because the stock 4l60e has internals that cannot handle sustained load, a number of issues may be caused by repeated 6,000+RPM shifts.

Built 4l60e transmissions can be shifted quite a bit higher, especially if they have been tuned to reduce shift timing. The difference in being able to shift a built 4l60e higher is that the internal components are much stronger than a worn out factory unit, and most high performance 4l60e builders know how to make them live in the higher RPM range.

If you have an application where you shift your vehicle at a higher than normal RPM range, it's always best to data log and see what mph and RPM your 4l60e is shifting at if you're looking to make changes. In a lot of situations, a 4l60e might not be making the 2-3 shift quick enough and ultimately bounces off the rev limiter prior to making a shift."

If you want to shift higher you're going to need hard parts. Ultra-Super-Mega trans rebuild kit or fancy Jmod-Reamed-Prolapsed valve body isn't enough. Components physically distort at higher RPM. Sure, you might be able to force it to go, but it's not going to keep going.

[slarsen47]

Just recently, after an engine swap (L31 with 411 pcm to 5.3 with green/blue pcm) my 4L60e has started acting up. Specifically, the 2-3 shift seems delayed. It's not slipping, flaring, or anything like that. It just doesn't shift when it is supposed to. For instance, I had the WOT shift set to occur at 6400rpm and 81mph and saw almost 6600 on my tach and 87 on the speedometer.

I lowered the mph down to 75mph and still see the delay. Sometimes at full throttle I just feels late, so I data logged today on a quick drive home from the gym. Nothing full throttle, but just fairly normal driving.

I see the the 2-3 shift commanded, and solenoids transition from off/on to off/off and the "trans current gear" go from 2 to 3 at the correct TPS/MPH but the RPM and Timing (Torque Management) don't respond until seconds later. When it shifts, it's nice and firm and feels normal.

Any insight?

Trans has about 50k miles on it since I built it, and was serviced last summer, fluid is and was clean.


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I looked at your hpt file and see your Trans Revs per Mile is 2718.574 in the Speedo section with 4.56 gear.

I don't know your tire size, but you should do a manual calculation to verify that the 2718 is correct.

I had this problem before using the wizard that gave a really bad number. After using the correct manual calculated number shifts right on the rpm.

[SiriusC1024]

Good thought, but shifting is commanded. Trans isn't capable of shifting.

[wlwarnke]

Running 35? tires (actually 34 or 34.5). Scanned MPH is accurate.

For now, I?ll retune and lower all shifts to 5800 or 6000 and see how it likes it.

Once I finish some house projects, I?ll either pull my 60 and figure it out, or source and 80 to build.

Is one better than the other for 6500 rpm shifting as far as cost to build?

Prior to the engine swap, my max rpm was 5100 and was perfect. New engine, it didn?t take too many rips for the 2-3 shift to start acting up.

Again big truck, driver, offroad, family hauler. Doesn?t get raced but it I want to be able to use the top end of the engines range occasionally without issues.

Also, why can?t I type apostrophe or quotes?

?Apostrophe?
?Quote?

[wlwarnke]

Both show up a question mark.

[HATEHPTUNERS]

If this is a full size truck then yes, an 80E is definitely the way to go. But, even with an 80E it is NOT going to like high RPM events... Keep in mind an 80E has HEAVY cast iron/steel drums inside... Think SUPER HEAVY drums... and those drums are not going to play nice with the bushings in the unit. When I build the 80's not only does EVERY bushing get replaced every time, there are several places we double up on the bushings to give the gear train more support. We can accomplish this by machining the drums, and shafts and stator tube to make the space we need for extra wide bushings. We machine the center support face and install a thrust bearing and relieve the load on the intermediate shaft-grounding all the rearward thrust from the direct, and forward drums, and the O/D planetary set this way into the case at the center support. There is an aluminum super drum that you can install, but they require periodic maintenance-meaning pulling the unit, tearing it down, and measuring/inspecting and replacing if/when necessary. I think your truck would be a good candidate for a turbo. Get a smaller turbo that will spool up quicker and start building power at lower RPM, and then limit the RPM in the tune to help save the transmissions life. Unfortunately, the 80E is also susceptible to damage and failure from high RPM events. You CAN make the power you need at lower RPM's without sacrificing the longevity of your transmissions.. think super charger... Turbo.. small shot of nitrous... This desire of yours to really wring out the engine in the higher rev's is going to be a costly road to travel regardless of what transmission you choose.

[SiriusC1024]

Every vehicle has limitations. Fuel cutoff is set to 6400 in my car. Dyno graph shows it's still flat in the torque even up there. There's a reason it took me a bit to get a feel for where redline is. The engine doesn't quit pulling. At all. Would I like to rev to 7000? Absolutely. My trans supports it (T56), the valvetrain supports it, but the '99 rod bolts sure as hell don't. I'm missing out on a lot of power, but you know what? 80k miles of fun and still going. It takes maturity to make the right decision. Take care of your ride, and it'll take care of you.

[wlwarnke]

So, my plan for now is set everything down to a tolerable 5800rpm and see if my Tranny is happier. Hoping I didn?t do any damage with the 10 or so 6400-6500 rpm 2-3 shifts.

The last 2 or 3 of them of them didn?t go well.

Driving normal, part throttle, the shifts feel normal.

If all is good, I?ll leave it until I have a chance to upgrade.

If all is not good, I?ll open her up and see whats what and figure out what upgrades need to be made to get me into the low 6000 range safely just so I?m not leaving some fun on the table.