Do you need to shim a starter on 2004 5.3 silverado

Generally speaking OEM dont shim starters because the tolerances are correct in manufacturing. If there are shims present the starter may have been replaced or rebuilt and the shims compensate for teeth mesh and reduce noise in startup.

Did you replace the starter yourself or have a garage do it? It sounds like the starter gear is not aligned properly with the ring gear on the engine. Sometimes a 'shim' is needed to make them align. Compare the old starter with the new one to see they are exact or is if a shim fell off when removing the old.

when mounting a chevy starter you must shim it down so it wont lock up when the bendix hits the flywheel..if it binds up it will burn up..there are different thicknesses of shims that fit between the block and the starter nose cone..use one or a combination of these to shim down enough that it wont drag..shim too far and it will spin out..I have owned chevys for years and have yet to see one that did not need shimmed down..these shims fit over the mounting bolts on the starter..

what size motor? 4.3? V8? The starter 4.3 is located on the passengers side on the bottom side of the motor. First disconnect the battery. , Look at the new starter and locate old one. Undo the nuts on the old starter. There should be 2-3 small wires all together on one terminal. Take them off. Take the larger nut off and take power cable off. Unbolt the 2 bolts holding the starter onto the block, pull old starter out. At this point have a look to make sure that the old starter doesn't have shims inbetween the starter and block. Some starters need a shim so that it lines up to the fly wheel. You may or may not need to replace these. My rule of thumb is that if they are there , use them again. Rebolt starter the opposite of removal. When you start the engine up, if you hear a loud grinding, or a winding noise and motor doesn't turn over, then you may have to put shims in. Good luck let me know how you make out. Cheers from Nova Scotia!!

smaller of the 2 wires is on the wrong terminal,or the starter needs a shim to move it away from the ring gear,if it is too close it won't come out.

The main factor on starters failing is heat. is there a heat shield between the starter and exhaust manifold or was there one? Also incorrect shims on the starter may do this too. if there was a starter shim. be sure to check the paperwork with the new starter to see if you need to use it. if it doesn't say anything about not using it, keep it in there.

Did you use the Shim's that come with new starters or check the gap with the little rod that come with the starterto see if the shim's are needed.

The problem seems to be with the solenoid on the starter motor that is why it is not engaging the flywheel. Please contact the nearest workshop as it can be repaired.

1) Disconnect Negative Cable on Battery
2) Starters on right-side Close to Trans. Bell Housing
3) Remove the 2-Starter Bolts and Shim if it's
if it has shims.
4) Remove the wires off Solenoid: Mark Them:
5) Remove the Heat Gaurd Over top of Starter:
6) Take Starter on Out.

To Re-Install Reverse the Procedure that you Removed the Starter. NOTE: the Shims if there was any are only nessary if the Casting of the Starter is not Exactly or Close to The Original.

Be sure that All the Wires you Took off the Starter Solenoid are put Back on the Exact Same Terminal. And Snug them up .Be careful not to Over Tighten,:
Specs on Bolts Are :
Torque Starter Battery Cable Nut to 90 inch lbs
Torque Smaller ingnition wier nuts to 18 Inch Lbs
Torque the 2- Starter Mounting Bolts to 35 FOOT lbs.
Remember if your Old Starter Had Shims the New one MIGHT need Shims.All Starters Casting are just a Little Different. like by thousands of an inch. So if you have problems you might have to remove or add shims,they come in different sizes. Hope this has helped you,Please let me know how this solution Helped. Thank You: From d_hubbs

1. Remove or disconnect the following:
   • Negative battery cables
   • Right front wheel and fender splash shield, on 6.6L engines
   • Turbocharger exhaust pipe, on 6.6L engines
   • Mounting bolts/nuts and shim, if used
   • Starter
   • Wires
   • Heat shield and bracket Exploded view of the starter motor-6.5L engine shown

To install:

1. Install or connect the following:
   • Heat shield and bracket. Torque the bolts to 13 ft lbs. (17 Nm).
   • Wires.Torque battery wire nut to 89 inch lbs. (10 Nm), and ignition nut to 18inch lbs. (2 Nm) on 6.5L engines. On 6.6L engines, tighten the solenoidnut to 30 inch lbs. (3.4 Nm) and the positive battery cable nut to 80inch lbs. (9 Nm).
   • Starter
   • Mounting bolts/nuts and shim,if used. Torque the bolts to 33 ft lbs. (45 Nm) and the nut to 75 inchlbs. (8.5 Nm) for 6.5L engines. For 6.6L engines tighten the starterbolts to 58 ft. lbs. (78 Nm).
   • Turbocharger exhaust pipe, on 6.6L engines
   • Right front fender splash shield and wheel, on 6.6L engines
   • Negative battery cables