4L60 Tune

Anyone enhanced a 4L60 tranny?
Please share information...

For firmer and faster shifts via HPT, yes. Also via the valvebody and related hard parts.

Hawkz28,
Thanks for that reply. Can you point me to the tables or info on that?

First and foremost, get a transmission cooler. Period. Bigger the better.

Definately poke around in the V8 forum. The 4L60 is used behind I4/5/6, as well as V6 and V8. That's where I gained most of my 'knowlege'. The methods aplied to other trannies applies as well in most cases. The 2 schools of thought that I've seen have been either adjust force motor current to increase line pressure and firm the shift, or increase the shift pressure values to firm the shift. I prefer the latter- but that's my opinion.

I also don't like the PWM of the TCC. I have adjusted it so it's either on or off. It is firm and feels like a 'half gear', as in 3.5, or 4.5. It's less wear and tear on it not having the TCC slipping, less heat, and that makes me and my 4L60E happy. Trans/Auto TCC/TCC duty cycle max 100, min 90.

The (IMHO) most unfortunate one for those of us w/ P12 (3.5 I5) is that we don't have access to desired shift time. We can log it to a degree, but not control it.

Hard parts- just shop around. Oregonperformancetransmission on ebay is a source I like to use for parts. Since we can't control the shift time via the tune, you can do it hydraulically. A corvette servo is a perfect example of this. This is more 'old school', but it gets the job done. I'd recommend getting your parts together and doing it all the next time you drop the pan for a filter change.

Hawkz28
Some great idea's... couple of questions regarding hardware info.

Quote:

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Originally Posted by HawkZ28

First and foremost, get a transmission cooler. Period. Bigger the better.

Definately poke around in the V8 forum. The 4L60 is used behind I4/5/6, as well as V6 and V8. That's where I gained most of my 'knowlege'. The methods aplied to other trannies applies as well in most cases. The 2 schools of thought that I've seen have been either adjust force motor current to increase line pressure and firm the shift, or increase the shift pressure values to firm the shift. I prefer the latter- but that's my opinion.

I also don't like the PWM of the TCC. I have adjusted it so it's either on or off. It is firm and feels like a 'half gear', as in 3.5, or 4.5. It's less wear and tear on it not having the TCC slipping, less heat, and that makes me and my 4L60E happy. Trans/Auto TCC/TCC duty cycle max 100, min 90.

The (IMHO) most unfortunate one for those of us w/ P12 (3.5 I5) is that we don't have access to desired shift time. We can log it to a degree, but not control it.

Hard parts- just shop around. Oregonperformancetransmission on ebay is a source I like to use for parts. Since we can't control the shift time via the tune, you can do it hydraulically. A corvette servo is a perfect example of this. This is more 'old school', but it gets the job done. I'd recommend getting your parts together and doing it all the next time you drop the pan for a filter change.

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Quest on this hardware upgrade on the trans with corvette servo add. Is this upgrade a project that can be done in the "backyard" you know in the driveway on your back. Or best to have done by a trans shop with auto trans fluid change @ 50K miles?

Easily done in your drive. I've done this to several transmissions so far in my driveway or in the garage- longest it ever took was 3 hours start to finish but I was adding a transgo shift kit and rebuilding the valvebody at the same time.

With the valve body- be sure to keep the bolts that secure the vb to the case in the correct order- if you get a couple of the lengths messed up, it will lock the trans out of gear.

Same goes for the check balls. Use some grease, KY jelly, or vaseline to hold them in the case before you put the seperator plate back in, as well as to keep them in the vb. If you don't get the check balls in the correct places, the trans won't operate correctly or at all.

Check on Coloradofans.com or 355nation.org for a LOT of how tos specific to the 355....not sure if these are on there, but you might even find some of them on the v8 sites since it's the same trans behind a lot of the v8s.

if your lookin for parts go to www.transmissioncenter.net they have every upgrade for the 4l60e, and if u want to upgrade to a 700r4 tranny! im gettn servos, and a upgrade combo kit for mine sometime soon!

Good information. There must be millions of these transmissions out there. Nice to know there are some upgrade options. Thank You.

there not to bad just the 3-4 is known for goin bad and having alot of problems but can be fixed with simple solutions to prevent it! hope u get what ur lookin for!

4L60E's are notorious for having problems. It's hit or miss, though. I got 198k on a 700R4 that was bone stock behind a CFI 350 w/ bolt ons, 229k on a 4L60E w/ cooler, Transgo, vette servo, .490 boost valve, pinless accumulators, and B&M shift Plus before the sunshell and a planetary gearset grenaded behind a 4.3L with bolt ons, and 44k out of my current 4L60E before a reaction carrier took a dump. A that point, all I had was a K&N drop in, gutted precat, and ram air on my 3.5, and no tune- trans was bone stock.

If you plan on keeping it a while, no matter what you do to the valve body and related parts, plan on a rebuild at some point.