Longevity of OEM distributor?

[highwaystar]

Distributor has spun for 290,000 miles. Bought truck new '94 5.7L Silverado. Replace or wait for failure?

 

[PlayingWithTBI]

Wait! You don't know what quality distributor you'll get anymore. If I could, I'd rebuild to OE one.

 

[Schurkey]

TBI distributor.

Disassemble for cleaning and inspection.

Gear condition
Shaft condition including magnet
Housing bushings (2) condition, and upper lube reservoir
Pickup coil condition
Module condition
Cap 'n' Rotor condition

Clean everything, replace parts as needed. fresh heat-sink compound under the module, reassemble. Don't forget to also inspect the wire harnesses (2) that plug into the module.

I'm thinking that there's a lube reservoir on the TBI distributor just like the older coil-in-cap HEIs. If I'm remembering this correctly, the plastic shield over the lube reservoir is brittle and no longer available. The lube itself has been everything from oil-wetted sawdust to white grease, to "special sauce" with a GM part number. This reservoir lubes the upper bushing. Cheap Chinese HEI distributors are known to have a lube reservoir...but the Commies "forgot" to drill the holes in the housing that allows the lube to reach the upper bearing. Brilliant! A lube reservoir that's entirely useless as the lube is prevented from going where it's actually needed.

The only two of these that are of genuine concern are the shaft/magnet and the housing bushings. If the shaft is scored, the bushings are probably toast. If the magnet is cracked, you need a new shaft. Shafts and housings are probably not available new, except as Communist Chinese knockoffs of dubious quality.

The only part I'd surely replace would be the pickup coil. They're not expensive, they are a pain in the *** to replace--the distributor shaft has to be removed; so replace the pickup coil when you've already got the distributor apart for inspection.

Better to have a "good used" Genuine Delco distributor than a brand-new Chinese knockoff; especially in the quality of the module.

 

[F4U-1A]

Distributor has spun for 290.000 miles. Bought truck new '94 5.7L Silverado. Replace or wait for failure?

Have had my 5.7 since new, good to know I have another 200,000 miles left on the distributor. Take me to circa 2070, both my grand mothers did live to 100. ( They were not driving at that age though) LOL

 

[FLJoe]

My 96 distributor is original with 510,000 miles and it's still fine. Just a new cap and rotor every hundred thousand or so. No way I'd take a chance replacing it unless it actually broke something. Most new parts I find are no where near the quality of what was new, especially if it's a "remanufactured."

 

[El Tigre]

Salvage yards here are filled with these Vortec 5.7's.
Some well cared for ,and those beat to death are obvious.
Easy to remove a distributor ,or two. Hell ,grab the whole intake.

 

[Nick_R_23]

I install a complete, new (not reman!) Napa distributor in every TBI truck I buy. I want to say they’re about $140-$150. They include a new cap and rotor as well. Not even close to being worth the effort of a rebuild when you can get the entire unit new for that price.

 

[Tpete562]

Distributor has spun for 290,000 miles. Bought truck new '94 5.7L Silverado. Replace or wait for failure?

In my opinion, wait, I'm on my second AutoZone distributor in about the last three years, I wish I would have just rebuilt the original.

 

[Schurkey]

I install a complete, new (not reman!) Napa distributor in every TBI truck I buy. I want to say they’re about $140-$150. They include a new cap and rotor as well. Not even close to being worth the effort of a rebuild when you can get the entire unit new for that price.

"New" generally means "Made in China". I'd be reluctant to trust the gear at the bottom, especially on a roller-cam.

There's so little to go wrong with a TBI distributor that rebuilding them is a snap--IF (big IF) you don't have worn bushings, and you can find a replacement main shaft.

 

[Nick_R_23]

"New" generally means "Made in China". I'd be reluctant to trust the gear at the bottom, especially on a roller-cam.

There's so little to go wrong with a TBI distributor that rebuilding them is a snap--IF (big IF) you don't have worn bushings, and you can find a replacement main shaft.

The Napa distributors are a pretty high quality part. I believe they’re still made in their South Carolina plant, here in the good ol’ USA.

Unless you have zero value of your own time or only want a bare minimum repair, there’s really no reason to mess around with rebuilding one these days. You get a completely new body (instead of replacing worn bushings), a completely new shaft (instead of replacing a worn shaft), new pickup coil (common failure point), new ignition module (another common failure point), and a new cap and rotor (which is likely due for replacement anyway).

If you think you can get all that and still save money including your labor, I’d love to see it.