1998 Chev siverado 350 5.7

[snoles]

Recently I had the transmission rebuilt in my 1998 Z71. Noticed that when I'm on the Highway under a load in the higher gears the truck starts to shake. No check engine light came on. Just had new spark plug wires put on and the timing reset.

[j cAT]

Originally Posted by snoles

Recently I had the transmission rebuilt in my 1998 Z71. Noticed that when I'm on the Highway under a load in the higher gears the truck starts to shake. No check engine light came on. Just had new spark plug wires put on and the timing reset.

check the fuel pressures,,,measure plug wire resistance this may be bad or wrong resistance..bad plugs..

it is possible the transmission/engine mounts or other hardware not properly assembled...

[snoles]

A new problem has accured. Engine light came on and had it checked .. Cylinder 1 and 3 misfire. Truck runs smooth in lower speeds but when you put a load on it in accelaration it starts to shake and seems to be misfiring. the engine light came on first blinking and them stopped. Spark Plug wires are brand new.

[Arrowshooter]

Should have your injectors checked.

[snoles]

Thanks, I'm making a visit to my mechanic tonight. Priced a new system (Spider) it's around $300.00 from Oreilly's.

[j cAT]

Originally Posted by snoles

Thanks, I'm making a visit to my mechanic tonight. Priced a new system (Spider) it's around $300.00 from Oreilly's.

before you buy anything check the fuel pressure

[j cAT]

Originally Posted by snoles

Spark Plug wires are brand new.

new means nothing ! plug wires are very , too often defective.