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Old 03-19-2017, 12:48 AM   #26
telly
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Re: Transmission? Poor acceleration.

Changed the PCV valve today. It was sludgy and didn't rattle when shaken. I then ran the truck for about 20 minutes and kept watch on the white/gray smoke coming from the exhaust (trying to burn off any excess oil that my have blown by while over-filled). After the white/gray smoke greatly diminished, I took the truck for a spin "around the block" (actually about a 3 mile loop). I don't seem to be having transmission troubles, at least no noise and/or clunky shifts. And, I still don't have any oil leaks that would indicate a main seal issue.

When I replaced the plugs, I did so one by one...remove plug wire, remove plug, insert plug, replace plug wire. I did not gap the plugs...I used them straight out of the box. It is HEI and when I reset the timing I did so with the vacuum advance unhooked and plugged and advanced to 12. I chose to reset the timing as I was getting some backfire upon deceleration...there is no backfire now after the reset.

The fluid in the tranny appears to be fine...not dark, although I haven't yet dropped the pan to see if there is any metal shavings in there.

*A bit of additional info...the truck will currently not spin its tires from a stop if traveling in a straight line, but it does have enough power to spin them when leaving a stop and turning onto another road.

**Another bit of additional info...I believe the engine to be a 350, but I can't be sure. I bought it from a guy who bought it from a guy...that guy supposedly built engines for racing and threw this one into this truck when the person he built it for didn't pay. The guy I got it from couldn't remember or didn't know what block was in it, and had no idea if it had been bored at all or what year. I haven't crawled back into it to take the numbers off the block. It may be a later 70's block, but I do believe it is a 350...just not certain that it's still a 350. With that information, what would you suggest the plugs be gapped to?
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Last edited by telly; 03-19-2017 at 12:54 AM.
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Old 03-19-2017, 08:47 AM   #27
cadillac_al
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Re: Transmission? Poor acceleration.

It sounds like you may have dodged a bullet here if you are still moving. Maybe the extra oil in the engine was doing something but I have no idea what. The plugs should be .045".
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Old 03-19-2017, 07:24 PM   #28
telly
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Re: Transmission? Poor acceleration.

Ok. So gapped the plugs to .045, checked the fluid levels again and tranny was fine but the engine oil was dark. That surprised me since I'd not driven the truck more than 10 miles since changing it last. So I drained and replaced that. Then ran the engine for a while and now I'm hearing a "tingy" clunk when I change between Drive and Reverse and vice versa.
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Old 03-19-2017, 08:03 PM   #29
garyd1961
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Re: Transmission? Poor acceleration.

That could be a u-joint in your driveshaft.
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Old 03-19-2017, 08:04 PM   #30
telly
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Re: Transmission? Poor acceleration.

Is that possibly due to the issues I've been dealing with or separate?
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Old 03-20-2017, 09:59 PM   #31
telly
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Re: Transmission? Poor acceleration.

Let me rephrase.

Could the u-joint be causing the loss of power/acceleration? Could the u-joint beginning to fail be caused from the other issues I've been dealing with?

I don't doubt that the u-joint needs to be replaced, and will do so.
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Last edited by telly; 03-20-2017 at 10:27 PM.
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