Cant get up to 45mph

SUBURBAN5

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You may have partially answered the question on my crew cab. I was going to replace cap/rotor and plugs; will be ordering them Monday once my paycheck comes in. Also I noticed that this truck doesn't seem to have an external transmission cooler, though it does have the oil cooler and power steering cooler. I would have thought a truck like that (1 ton crew cab) would've had a trans cooler?
2500 I would think so too but not necessarily. I'm surprised but then again mine didn't come with a power steering cooler but yet I have everything else accept the rear hitch lol. I think I may have found the misfire cause....
 

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You may have partially answered the question on my crew cab. I was going to replace cap/rotor and plugs; will be ordering them Monday once my paycheck comes in. Also I noticed that this truck doesn't seem to have an external transmission cooler, though it does have the oil cooler and power steering cooler. I would have thought a truck like that (1 ton crew cab) would've had a trans cooler?
That's weird... it should have two trans coolers (one in pass side of rad that also routes to square one in front), one oil cooler in driver side of rad, and one tall skinny ps cooler
 

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Two of those distributor cap terminals look terrible, the rest look pretty OK.

Trace and test the plug wires (and plugs) for those two terminals. I bet you find high resistance in the plug wires, corroded connection at the spark plug or distributor cap, or some other source of unusually-high firing voltage.

Replacing the cap doesn't change the root-cause of the high firing voltage. That's the true cause of the misfire. (Most likely)
 

SUBURBAN5

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Two of those distributor cap terminals look terrible, the rest look pretty OK.

Trace and test the plug wires (and plugs) for those two terminals. I bet you find high resistance in the plug wires, corroded connection at the spark plug or distributor cap, or some other source of unusually-high firing voltage.

Replacing the cap doesn't change the root-cause of the high firing voltage. That's the true cause of the misfire. (Most likely)
I was hoping this is the most likely cause... I'm letting the engine cool off after a test drive and will pull the plug and wires. I'm already planning on replacing it. Off the bat I saw the wires on bank 2 have some burnt signs on the wires. I didn't see exposed wires but I need to pull them off and examine closer. As for the plugs #3 is the biggest problem child so I want to pull that one and see how it looks
 

SUBURBAN5

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I'm not much of a spark plug wizard but can anybody dissect what these are telling me?. The darker reddish one is piston 3.
 

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SUBURBAN5

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Plugs look decent. The color is from fuel additive/s in fuel. No signs of oil and/or gas foul. Check the wire resistance in each wire.

Has the pick up coil ever been replaced?
No the coil original. Wouldn't that make it have a hard time starting if the coil was bad?
 

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No the coil original. Wouldn't that make it have a hard time starting if the coil was bad?
Not necessarily. Electrical issue/s often will rear themselves when heat and a certain condition allows for the issue to present itself. Example....Mine (94 P30 chassis RV) reared itself twice when I would come to a stop the engine would just shut off as if someone reached over and turned key off. Pulled the distributor replaced the 'pick up coil' and inspected the reluctor carefully for crack/s (there were none). Since then (2+ years) not a single episode of shutoff. If you pull the distributor replace the pick up, coil, ICM, cap and rotor and inspect the reluctor closely. Use only AC Delco parts. Also check the shaft for excess play (side-side). I had ~57K miles on the engine at the time.

Here's a pic of the old coil...
 

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