2000 Silverado Surging at highway speed

[b_l_bailey]

As of recent, I have noticed my truck has a very slight surge when I'm traveling 50-60 MPH down the highway. It has a 5.3L engine. I'm at a loss at this point. Within the past couple of years I have replaced the fuel pump, fuel pressure regulator, and the MAF sensor. I'm not pulling a code that would lead me in that direction. The only code I have is the gas cap code which I've had for months now. I was wondering if the plug wires would cause this, but don't want to waste the money until I see if anyone else has had a similar issue.

[j cAT]

Originally Posted by b_l_bailey

As of recent, I have noticed my truck has a very slight surge when I'm traveling 50-60 MPH down the highway. It has a 5.7L engine. I'm at a loss at this point. Within the past couple of years I have replaced the fuel pump, fuel pressure regulator, and the MAF sensor. I'm not pulling a code that would lead me in that direction. The only code I have is the gas cap code which I've had for months now. I wondering if the plug wires would cause this, but don't want to waste the money until I see if anyone else has had a similar issue.

testing/inspection of everything is required plugs ,wires, cap, rotor, distributor, fuel pressure,clean maf/throttle body, replace PCV and hoses check for vac leaks..

possible tranny/torque converter fluid issues....dexronIII...

[b_l_bailey]

Originally Posted by j cAT

testing/inspection of everything is required plugs ,wires, cap, rotor, distributor, fuel pressure,clean maf/throttle body, replace PCV and hoses check for vac leaks..

possible tranny/torque converter fluid issues....dexronIII...

I just cleaned the throttle body and my vac hoses are fine. No cap and rotor on this engine. Fuel pressure is within range. What would the symptoms of the torque converter be? Would it still surge when the lock up is in? Transmission fluid is full and looks clean.

[j cAT]

Originally Posted by b_l_bailey

I just cleaned the throttle body and my vac hoses are fine. No cap and rotor on this engine. Fuel pressure is within range. What would the symptoms of the torque converter be? Would it still surge when the lock up is in? Transmission fluid is full and looks clean.

the 5.3l vortec engine with the 12 inch plug wires?

[b_l_bailey]

I'm sorry, yes. I had put 5.7L ...... Long day!

[j cAT]

Originally Posted by b_l_bailey

I'm sorry, yes. I had put 5.7L ...... Long day!

this then could be the intake manifold leak vacuum, the crank position sensor under the starter motor...rather than the mentioned distributor items for a 5.7L..

when the speed is around the 50mph area the engine is known to have this issue if the fuel pressure is low..this engine is 53-62psi..

measure plug wire resistance 550-650 ohms..a/c plugs only,,this engine is picky..

then the transmission . some have had this if the fluid was force flushed rather than droping pan and replacing the transmission fluid/filter ...you must also use the new dexronVI,,,dexron III is bad for this transmission thats why its been changed...hopefully its simple not a tranny problem.

[b_l_bailey]

I will check the intake and the wires and post my findings. Probably won't happen until saturday. Thanks for the tips.

[j cAT]

Originally Posted by b_l_bailey

I will check the intake and the wires and post my findings. Probably won't happen until saturday. Thanks for the tips.

see what you find ..give a post with your results..

I have the 2000 silverado 1500 5.3L LT 4dr..4X4..since new so far no major problems..125,ooomi..

the rear brakes and park brakes I finally modified so now thats all working. never worked new correctly.

[b_l_bailey]

Well....... I have ruled out the vac leak, intake, ignition. The more I have driven it, the more I am sure it is a transmission issue. That sucks... To top it off, I did take the initiative to change the fluid and filter (using castrol Dexron VI). This is a deep pan transmission, so therefor it is nearly impossible to get the pan off. The pan will however come down far enough to at least change the filter, so I did that, cleaned out the pan, etc. Got her all back together, and I find out the 2-3 solenoid is not working. Somehow I disturbed the connection. Fun stuff. Hopefully I did not break it.

[2000CAYukon]

The solenoids are near the rear of the tranny and if you are not careful, you can break a wire off one of the solenoids. On my 2000 Yukon, I have to remove the gear selector bracket and drop the front drive shaft to get the pan off.

The surging can be caused by the TCC Regulator valve that can be fixed without removing the tranny. http://www.sonnax.com/announcements/77754-04K.pdf

//2000CAYukon

[j cAT]

the torx screws need be removed to remove or be able to move enough to remove the deep pan ...

I use 1/4 ratchet with adaptor to hold the torx small sized bits to extract the screws...

with the deep pan there is a drain plug with the pan removed this is then the time to heat up this fitting with a torch and lossen the locktight ..this will help next time..in draining most of the fluid...

the torx srews need anti seize on the threads this will be easier also.

when was the last time you replaced the fluid ?