P1870, 4L60E, PWM delete etc.

[tayto]

Can the "PWM delete" be effected with a "tune" to the ECU? The ECU controls this behavior, so it would seem possible / likely.

I would much rather do this on the computer than on my back.

I haven't looked at the transmission parameters for the ECU on my '98 for this parameter, yet; this thought just came to my mind so I posted it.

(@NickTransmissions, nice write-up in the prior post )

i would do it in the valve body. there is a simpler and cheaper fix, just flip the inner valve on the tcc pwm valve and reinstall

 

[Peavey]

AC Delco, Borg Warner or Rostra.

AC Delco for the shift solenoids and pressure switch manifold

Borg Warner for the electronic pressure control solenoid (sometimes listed as a "force motor")

Rostra for the wiring harness, 3-2 control solenoid and PWM solenoid.

In addition to the online retailers @Deancr11 provided, Cobra Transmission and Transpartswarehouse.com should also have what you need and ship overseas.

Allright! Thank you so much for your replies (@Deancr11 as well)! I´ll do some research and see where it makes most sense to order parts. Are there any other parts which are a "must or nice to have" while doing this operation aside from the kit and the electrical bits? Obviously one would need a pan gasket and new filter but isn´t there, for instance, some sort of gasket attached to the valve body that needs replacing too? Separator plate and check balls? Something more?

I apologize again for asking so many questions, but this is totally new territories to me - I only know what the basic components in the transmission are called but have only little or no idea what or how they operate together. I´m also asking since this repair will be performed (given that I quit biting my finger nails over it) with the transmission still in and the rig sitting on jack stands on my driveway.

Again, thank you for your replies and thank you to everyone else sharing your knowledge in other threads in an amazing forum!

Best regards

//Johan

 

[Vic327]

That first post that says look up how to get to the valve without removing the valve body is the best advice. You can use a heavy spring or piece of tubing to lock out the converter slip and make it on off. Aluminum accumulator pistons should be on the list if you pull the valve body, for sure if you go with the shift kit. Get the one for the 2nd accumulator if you don't drop the valve body. Also follow the directions about the servo pin length with the shift kit if you use it.

 

[Peavey]

Hi again and thank you all for your replies so far!

I´ve looked around and Oregon Performance Transmission seems to have what I should be looking for in terms of both shift correction kit and electronics (like both @Deancr11 and @NickTransmissions suggested earlier in the thread, thanks!).

OPT have a kit with “everything” included, such as the Transgo SK4L60E, gaskets, sep.plates, pistons, corvette servo etc, which, at least to me, seems like a good, solid option.

There is however an option when ordering the kit for a .470 or .490 boost valve. I understand (or at least think I understand) what a boost valve does and from what I´ve read, it makes sense to replace it as well, but which one should I choose (if any)?

Also, do you think that the kit with the Transgo SK4L60E, a corvette servo and (maybe?) one of the boost valves would make the transmission shift too hard/aggressive for normal driving?

Link to the OPT shift kit: https://www.oregonperformancetransmission.com/product/OPT-4L60E-VB1.html

Link to the solenoid kit: https://www.oregonperformancetransmission.com/product/OPT-4L60E-EL.html

Really appreciate any input you could give me.

Thanks again!

 

[NickTransmissions]

Hi again and thank you all for your replies so far!

I´ve looked around and Oregon Performance Transmission seems to have what I should be looking for in terms of both shift correction kit and electronics (like both @Deancr11 and @NickTransmissions suggested earlier in the thread, thanks!).

OPT have a kit with “everything” included, such as the Transgo SK4L60E, gaskets, sep.plates, pistons, corvette servo etc, which, at least to me, seems like a good, solid option.

There is however an option when ordering the kit for a .470 or .490 boost valve. I understand (or at least think I understand) what a boost valve does and from what I´ve read, it makes sense to replace it as well, but which one should I choose (if any)?

Also, do you think that the kit with the Transgo SK4L60E, a corvette servo and (maybe?) one of the boost valves would make the transmission shift too hard/aggressive for normal driving?

Link to the OPT shift kit: https://www.oregonperformancetransmission.com/product/OPT-4L60E-VB1.html

Link to the solenoid kit: https://www.oregonperformancetransmission.com/product/OPT-4L60E-EL.html

Really appreciate any input you could give me.

Thanks again!

You can order either boost valve, the increase in boost valve ratio doesn't mean firmer shifts, it means more fluid volume available thus better/faster pressure rise in the apply circuitry at higher throttle angles. That translates to clamping force exerted on the clutch packs, which means the clutch is less likely to slip in the face of increased engine torque/HP that it sees when you go WOT to pass folks or when racing, etc.

Shift firmness, on the other hand is determined by clutch apply speed. The faster a clutch applies, the firmer it will be all other things (including converter stall speed) held equal. That is determined by a variety of factors, chief among them, orifice hole sizing in the spacer plate.

If you follow Transgo's shift kit instructions, you will have pleasant part-throttle shifting and crisp (but not harsh) shifting at higher to WOT throttle angles.

As far as OPT 'shift kit' (they don't make shift kits, they're selling bundled parts) - I'd price out those things individually to see if it's cheaper that way vs buying their 'bundled kit'...The paper/rubber kit is prob $60ish, shift kit is $50 or so, Vette servo is $15, filter is $10 and Sonnax Pinless accumulator pistons are $15 each (you don't really need one for 2nd gear accumulation, just 4th gear).

 

[Peavey]

You can order either boost valve, the increase in boost valve ratio doesn't mean firmer shifts, it means more fluid volume available thus better/faster pressure rise in the apply circuitry at higher throttle angles. That translates to clamping force exerted on the clutch packs, which means the clutch is less likely to slip in the face of increased engine torque/HP that it sees when you go WOT to pass folks or when racing, etc.

Shift firmness, on the other hand is determined by clutch apply speed. The faster a clutch applies, the firmer it will be all other things (including converter stall speed) held equal. That is determined by a variety of factors, chief among them, orifice hole sizing in the spacer plate.

If you follow Transgo's shift kit instructions, you will have pleasant part-throttle shifting and crisp (but not harsh) shifting at higher to WOT throttle angles.

As far as OPT 'shift kit' (they don't make shift kits, they're selling bundled parts) - I'd price out those things individually to see if it's cheaper that way vs buying their 'bundled kit'...The paper/rubber kit is prob $60ish, shift kit is $50 or so, Vette servo is $15, filter is $10 and Sonnax Pinless accumulator pistons are $15 each (you don't really need one for 2nd gear accumulation, just 4th gear).

Thank you very much Nick for a well written and understandable answer!

I went ahead and ordered the OPT kit along with the electronics kit (added a .490 boost valve, a 4th gear piston and some assembly grease too). Hopefully it will arrive rather soon and I´ll do my best to get it installed (I´ve started to watch your Youtube channel as well @NickTransmissions for some inspiration and technical tips ).

I´ll be back with (hopefully) positive news.

Thanks again!

//J