Transmission issue

[ukrkoz]

I have 07 Tahoe LT
It had engine work done but, same time, had VERY harsh 1/2 shifts.
So, the guy who worked on it, replaced all shift solenoids and 1/2 accumulator. Well, or so he says.
He brought truck back today and this is what I have;
2nd gear shift at 3500 rpm. There is no way in the world this is normal.
Cruising FWY at 65 mph, RPMs sit at 2500. I had Silverado with 5.3L Vortec and am pretty sure RPMs at FWY speed should be below 2000 for 60 mph, somewhere around 1700-1800 cruising.
So I figured, it does not shift into OD. Took truck out 20 min ago, there is no RPM change manually shifting to 3 and back to OD. It apparently sits in 3rd gear at the best.
He is supposed to "swing by" tomorrow to check on it but, before he shows up, I'd love to be prepared and know, what is causing this situation. According to him, he bought entire solenoids kit and replaced all solenoids and valve body gasket.
ATF is burnt out and brown. I KNOW what new ATF looks like, though he charged me for filter and ATF refill and I had done countless partial drains and refills and ATF always was at least pinkish after partial drain.
I'd absolutely appreciate suggestions.
No error codes otherwise.

 

[BG1988]

I have 07 Tahoe LT
It had engine work done but, same time, had VERY harsh 1/2 shifts.
So, the guy who worked on it, replaced all shift solenoids and 1/2 accumulator. Well, or so he says.
He brought truck back today and this is what I have;
2nd gear shift at 3500 rpm. There is no way in the world this is normal.
Cruising FWY at 65 mph, RPMs sit at 2500. I had Silverado with 5.3L Vortec and am pretty sure RPMs at FWY speed should be below 2000 for 60 mph, somewhere around 1700-1800 cruising.
So I figured, it does not shift into OD. Took truck out 20 min ago, there is no RPM change manually shifting to 3 and back to OD. It apparently sits in 3rd gear at the best.
He is supposed to "swing by" tomorrow to check on it but, before he shows up, I'd love to be prepared and know, what is causing this situation. According to him, he bought entire solenoids kit and replaced all solenoids and valve body gasket.
ATF is burnt out and brown. I KNOW what new ATF looks like, though he charged me for filter and ATF refill and I had done countless partial drains and refills and ATF always was at least pinkish after partial drain.
I'd absolutely appreciate suggestions.
No error codes otherwise.

clutch is worn out. the RPM will vary depending on the final gear ratio and tires used..

 

[ukrkoz]

It's automatic.

 

[Big Mama]

Automatics have clutch discs too. How long ago was your last trans fluid changed and how many miles on your rig?

 

[wsteele]

I would take it to a quality transmission shop, have them look it over.

 

[ukrkoz]

Of course. It just sounded like manual clutch. Far I recall, before repair, there was only harsh 1/2 shift. After repair, 1/2 shift is only at 3500 rpm, unless I go very slow and fool it by letting gas pedal off. What is not practical driving by any means.
142000 miles. Allegedly, mechanic, who worked on trannie, did drain and fill ATF, but it's still brown and stinky.

 

[swathdiver]

I have 07 Tahoe LT
It had engine work done but, same time, had VERY harsh 1/2 shifts.
So, the guy who worked on it, replaced all shift solenoids and 1/2 accumulator. Well, or so he says.
He brought truck back today and this is what I have;
2nd gear shift at 3500 rpm. There is no way in the world this is normal.
Cruising FWY at 65 mph, RPMs sit at 2500. I had Silverado with 5.3L Vortec and am pretty sure RPMs at FWY speed should be below 2000 for 60 mph, somewhere around 1700-1800 cruising.
So I figured, it does not shift into OD. Took truck out 20 min ago, there is no RPM change manually shifting to 3 and back to OD. It apparently sits in 3rd gear at the best.
He is supposed to "swing by" tomorrow to check on it but, before he shows up, I'd love to be prepared and know, what is causing this situation. According to him, he bought entire solenoids kit and replaced all solenoids and valve body gasket.
ATF is burnt out and brown. I KNOW what new ATF looks like, though he charged me for filter and ATF refill and I had done countless partial drains and refills and ATF always was at least pinkish after partial drain.
I'd absolutely appreciate suggestions.
No error codes otherwise.

He messed up somewhere along the way in assembly. May have forgot a check ball or used the wrong gasket. Either way, it very likely needs to be rebuilt again. Are you near Amarillo, Texas by chance?

 

[ukrkoz]

Sorry, I am in PacNW. A bit of a drive, he he.

Anyhow. Based on this:


2. 1-2 shift does not happen at WOT until you let off the gas: Best case: try replacing the TPS. Middle case: leak in the 2nd gear apply circuit (servo assembly or 1-2 accumulator). Doublecheck by using the pressure gauge and watch for a big drop when the PCM commands 2nd gear. Worst case: poor line pressure rise (see below).


3. 1-2 Shift shudder at WOT; delayed or abnormal 1-2 shift; There's a problem ONLY on the 1-2 shift: 1-2 accumulator piston cracked or stuck cocked in the bore. Check the yellow spring inside the accum housing for breakage. Also, if the accumulator housing walls are scored, the housing must be replaced. Easy fix in the pan.


4. 1-2 shift is delayed and harsh, may not shift into OD: Check TPS for smooth and linear electrical response over the entire range of motion. If not, replace.

I replaced TPS. It actually helped. Shift point moved from 3500 RPM to 2500 RPM and even to 2300 RPM on hot trannie. Shift is a bit harsh, but works. OD still is out.
Truck also threw O2 sensor code, so I have one on order. I pulled current one out, it's B1S2 and it was all sooted up.
Basically, all I have left is trannie problem.
So back to my g'ol daily driver 98 MGM.

 

[thompsoj22]

If you had the trans repaired and upon "initial inspection" of the trans fluid by you it was "brown and burnt smelling" than dont allow your mech to touch anything more. Find a new mech as you have been ripped off! Dont get all pissed or anything, Just be more cautious with your next choice for trans repair. Reputable, Refrences and warranty.

 

[ukrkoz]

That's the plan. I'll give this mech few days, as he "was on it", then take it to a guy I know for what, about 33 years. He has life long transmission mech who did my MGM trannie last year. I'll deal with the last one as it develops.
Not angry. Actually, quite at peace. It's just expense, I like truck. Rides very nice. I'm 6'2'', feels very good.