Tranny/torque Converter Problems?

[kokanee]

I have a '99 Silverado 5.3

A few problems which may be related, both are noticably worse when towing my travel trailer (5000 lbs):

 

1. Transmission shifts sluggishly from 2nd to 3rd gear. I can hear the transmisison shift (use tow/haul and tow in 3rd) and instead of a firm sharp shift there is a delay; the engine will start to gain a few hundred rpm during the shift and then eventually completes the shift. It does this when I am not towing but it is not nearly as bad.

 

2. When backing up I have to rev the engine a fair bit before the truck starts to move, when it moves there is a noticable lurching, not smooth like it should be.

 

3. I have a hesitation when accelarating from a stop, from around 2000-2500 rpm the truck seems to stumble and then suddenly the power kicks in and runs strong. This is only noticed from a dead stop and not under normal driving.

 

Transmission was checked for this problem a year ago, the pan was dropped and inspected and serviced. No metal found. Computer was reprogrammed.

[bobcat5544]

Posible Causes for the Trans

Valve Body Assembly 2-3 Shift valve stuck or sticking will cause both trans problems

 

Far as the hesitation the truck will need to be hooked up to a scanner to figure out what the cause it.

[kokanee]

Posible Causes for the Trans

Valve Body Assembly 2-3 Shift valve stuck or sticking will cause both trans problems

 

Far as the hesitation the truck will need to be hooked up to a scanner to figure out what the cause it.

 

Thanks BobCat, can the shift valve be tested and replaced seperatley or does it mean a tranny rebuild??

[bobcat5544]

With out seeing the truck it is not 100% that the shift valve is the problem with out doing test on it. To test it requires specail tools, But it is inexpensive to replace the 2-3 shift soleniod about $30.00 for the 2-3 shift soleniod $15.00 for fluid $25.00 transmission pan gasket and about 2.0 hours time

 

To replace the 2-3 shift valve.

 

Remove the transmission oil pan

Locate the 2-3 shift valve # 367B (see diagram)

Unplug the shift soleniod #367B

Remove the retainer clip # 395

Pull out shift valve (be carefull the valve does not shoot out # 368/369)

 

Install in reverse order and re fill trans 4-5 quarts

 

[kokanee]

With out seeing the truck it is not 100% that the shift valve is the problem with out doing test on it. To test it requires specail tools, But it is inexpensive to replace the 2-3 shift soleniod about $30.00 for the 2-3 shift soleniod $15.00 for fluid $25.00 transmission pan gasket and about 2.0 hours time

 

To replace the 2-3 shift valve.

 

Remove the transmission oil pan

Locate the 2-3 shift valve # 367B (see diagram)

Unplug the shift soleniod #367B

Remove the retainer clip # 395

Pull out shift valve (be carefull the valve does not shoot out # 368/369)

 

Install in reverse order and re fill trans 4-5 quarts

 

 

I had the 2-3 shift valve replaced and still have the 2-3 shift slipping under moderate to hard acceleration. What do I look at next?