My girlfriend's brother has an Express 2500 with the 4.8 and it has erratic oil pressure readings and a slight lifter tap that wasn't there when he bought it used so we've decided to replace the oil pump. Has anyone replaced one of these ?? If so can somone tell me what's involved. Do I have to drop the oil pan because it doesn't seem so it looks like it bolts to the front of the engine block and is either cam or crank driven. Any and all help is appreciated.

 

Sorry buddy, but you are not going to do it with a socket set and a Haynes manual.

It's not the oil pump, it is the bearings. More then likely the cam bearings are out of the motor.

Now you are there and I am here, but I don't know what was in the motor when they bought it or how many miles is presently on the motor. Who the previous owner was - or what ever.

The old first generation V -8 265 - 400 SBC - you could probably try to replace the oil pump by just dropping down the oil pan and removing the old pump and putting in a new pump.

With the new generation 4.8 / 5.3 - 6.0L - forget it.

BUY a Haynes manual and look at the engine rebuild section and then look at the grocery list of tools needed and then price a new crank kit and a new oil pump and all the gaskets and associated hardware and see if it doesn't come to more then what a used or rebuilt engine costs.

There is no easy way to fix your problem - other then a complete rebuild.

 

http://www.flatlanderracing.com/rebuildkitschevy.html

<table style="border-collapse: collapse;" width="636" border="1" bordercolor="#a6a6a6" cellpadding="2" cellspacing="0" height="4352"><tbody><tr><td colspan="7" valign="top" align="left">292 / 4.8L

<table style="border-collapse: collapse;" width="636" border="1" bordercolor="#a6a6a6" cellpadding="2" cellspacing="0" height="4352"><tbody><tr><td valign="top" align="left" bgcolor="#000000"> Application</td> <td valign="top" align="left" bgcolor="#000000"> Part #</td> <td valign="top" align="left" bgcolor="#000000"> Notes</td> <td valign="top" align="left" bgcolor="#d9f0ff" nowrap="nowrap"> Re-Ring (RK)</td> <td valign="top" align="left" bgcolor="#e6fff2" nowrap="nowrap"> Overhaul (OK)</td> <td valign="top" align="left" bgcolor="#eeeeee" nowrap="nowrap"> Master (MK)</td> <td valign="top" align="left" bgcolor="#ffffff"> HP Kit</td></tr></tbody></table>
</td> </tr> <tr> <td valign="top" align="left" height="24">Chevy 292 4.8 (99-01) Truck, 16 valve eng., Vin "V"</td> <td valign="top" align="left" height="24" nowrap="nowrap">1229</td> <td valign="top" align="left" height="24" nowrap="nowrap">2,4</td> <td valign="top" align="left" bgcolor="#d9f0ff" height="24" nowrap="nowrap"> $529</td> <td valign="top" align="left" bgcolor="#e6fff2" height="24" nowrap="nowrap"> $755</td> <td valign="top" align="left" bgcolor="#eeeeee" height="24" nowrap="nowrap"> $999</td> <td valign="top" align="left" height="24" nowrap="nowrap">-</td> </tr> <tr> <td valign="top" align="left" height="24">Chevy 292 4.8 (02-03) Truck, 16 valve eng., Vin "V"</td> <td valign="top" align="left" height="24" nowrap="nowrap">1229-A</td> <td valign="top" align="left" height="24" nowrap="nowrap">2,4</td> <td valign="top" align="left" bgcolor="#d9f0ff" height="24" nowrap="nowrap"> $469</td> <td valign="top" align="left" bgcolor="#e6fff2" height="24" nowrap="nowrap"> $695</td> <td valign="top" align="left" bgcolor="#eeeeee" height="24" nowrap="nowrap"> $985</td></tr></tbody></table>

 

Have you check the oil pressure with an external gage? might be worth checking to insure its not a sending unit or gage issue and its easier then tearing into the engine right off the bat....