2002 Chevy Tahoe lockup problem

[ljacob]

I just a 2002 Chevy Tahoe I was delivered on a car dolly with the drive shaft in it still probably 50 miles I would down shift into first so I replaced the a/b shift solenoid and the downshift solenoid but I didn't change the torque converter lockup solenoid I shifts fine now but I'm just unclear if the lockup is doing as it should I will get it up to 50 and cruising as normal between 2000 and 1500 rpm then it drops down to almost 1100 rpm and I have no throttle response until I pressed the pedal a good way in and then it jumps up to 2000 rpm and I have throttle response as normal until I get cruising at that speed for a minute

question is does it sound like a bad torque converter or torque converter solenoid or is it normal the truck does have 35s on it

 

[Fless]

Welcome to TYF. Moved you here from "Site News" since this is a specific Engine & Drivetrain issue for the 2000-2006 MYs.

 

[ljacob]

Welcome to TYF. Moved you here from "Site News" since this is a specific Engine & Drivetrain issue for the 2000-2006 MYs.

4.8 4l60e

 

[Marky Dissod]

Can't say for sure if the behaviour is normal 'cause I don't know if your pcm is tuned or not.
That said, the GM OE tune 'wants' to upshift to 3rd and then 4th as soon as reasonably possible,
and also to lock the TCC as soon as reasonably possible once it's in 3rd or 4th.
Sometimes it may sound like a downshift, but it's actually the TCC locking, which almost always lowers RpMs a bit more.

If your foot goes beyond about 33% TPS, it usually unlocks the TCC, but it may or may not downshift,
depending on how fast the vehicle is going.
If your foot goes over about 50% TPS, it usually downshifts after unlocking the TCC.

 

[Joseph Garcia]

@NickTransmissions

 

[ljacob]

Can't say for sure if the behaviour is normal 'cause I don't know if your pcm is tuned or not.
That said, the GM OE tune 'wants' to upshift to 3rd and then 4th as soon as reasonably possible,
and also to lock the TCC as soon as reasonably possible once it's in 3rd or 4th.
Sometimes it may sound like a downshift, but it's actually the TCC locking, which almost always lowers RpMs a bit more.

If your foot goes beyond about 33% TPS, it usually unlocks the TCC, but it may or may not downshift,
depending on how fast the vehicle is going.
If your foot goes over about 50% TPS, it usually downshifts after unlocking the TCC.

It's a oe tune and yeah I can feel it go Into 4th then lock up and then I have terrible throttle response until till I would press the pedal a little bit and then I think the torque converter unlocked and I have throttle response again it is on 35s that might be a contributing factor also I just don't like how low the rpm go with the bad throttle response

 

[Marky Dissod]

Because GM heavily favoured POTENTIAL MpGs over throttle response and geartrain durability.
I also have an '02 Tahoe (Z71). Not sure I'd be able to tolerate driving it without a pcm tune.
Given that the OE tire for these was 31.6" tall or shorter, your 35" tall tires are slowing your truck down even more.
You need 4.10 even more urgently than I do.

 

[ljacob]

Because GM heavily favoured POTENTIAL MpGs over throttle response and geartrain durability.
I also have an '02 Tahoe (Z71). Not sure I'd be able to tolerate driving it without a pcm tune.
Given that the OE tire for these was 31.6" tall or shorter, your 35" tall tires are slowing your truck down even more.
You need 4.10 even more urgently than I do.

Yes I do a 4.10 is next on the list I think that will solve my issues if not gonna try a tune the PCM thanks for the information

 

[Marky Dissod]

Yes I do. 4.10 is next on the list. I think that will solve my issues. if not gonna try a tune the PCM. thanks for the information.

In a hypothetical scenario where I could only have one, 4.10, instead of the pcm tune.
That said, your 4L60E will still upshift too early, make you add lots of throttle before downshifting, and will not address any of your original post complaints.
In the real world, I have already taken the pcm tune, and am budgeting towards 4.10 for both axleS.

Since the pcm tune is (almost certainly) cheaper than a 4.10 axle (nevermind two), I recommend the pcm tune first, whether or not you do 4.10 sooner or later.

 

[ljacob]

In a hypothetical scenario where I could only have one, 4.10, instead of the pcm tune.
That said, your 4L60E will still upshift too early, make you add lots of throttle before downshifting, and will not address any of your original post complaints.
In the real world, I have already taken the pcm tune, and am budgeting towards 4.10 for both axleS.

Since the pcm tune is (almost certainly) cheaper than a 4.10 axle (nevermind two), I recommend the pcm tune first, whether or not you do 4.10 sooner or later.

Okay that makes sense so start with the tune and then get so 4.10s the tune will make the truck happy and the 4.10 will make me happy