1996 Chevrolet P30 oil leak and transmission problem

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JuggaloCujo
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Joined: Mon Dec 31, 2012 1:04 am

1996 Chevrolet P30 oil leak and transmission problem

Unread post by JuggaloCujo » Mon Dec 31, 2012 1:08 am

I have a 1996 Chevrolet P30 UCBC Step Van with a 5.7L 350 engine.
It has sat for a year without starting. Everything was fine when it was parked.
While it sat a huge tree limb fell on the hood and bent the frame.. luckily it didn't appear to break anything other then the hood assembly and bending the frame. No radiator leaks or anything.
The truck before it was parked had an oil leak, suspected to be coming from the oil pan. I picked the van up 2 days ago, dumped 5 ounces of pure acetone into the tank which had around 24 gallons in it and added another 15 gallons of fresh gas, as well as some Chevron Techon fuel additive.
I checked all of my fluid, replaced my battery (Napa Legend 75) and it started right up, I warmed it up for a good 15 minutes to get everything flowing and loosened up, then it was time to drive it 75 miles home.
The (engine) ran awesome, and it should have it has always been well maintained and I have always run synthetic fluids in every place that I can.
It has a K&N air filter, and new plugs.. I've always used oem and ac delco parts.

When I hit the road the transmission did not want to stay engaged, it would engage, pick up speed, pop back out, the engine would rev loud and then it would jerk back in, this was a constant problem and I was not able to exceed 45mph. I double checked the trans fluid everything was fine. It would drive fine in the city though (low speed, low rpms) I also noticed that while in neutral revving the engine made the speedometer move, And the speedometer would not move past 35mph. while driving. When I got it home I pulled the engine cover and started my investigation.. I found that an oil pressure sensor (located under the distributor cap) is the real source of the leak.. it is shooting oil right out into the electrical connector and it is dripping off of the transmission and onto the oil pan and exhaust. Other than this one problem I have no idea what the issue could possibly be. My name is John and I am desperate for information. I can be reached via phone @ xxx-xxx-xxxx or e-mail xxxxx@xxxxx Thank you for your time and any help you can provide!

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ProTech
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Re: Chevrolet P30 HELP!!

Unread post by ProTech » Tue Jan 01, 2013 10:08 pm

Well, this could be something as easy as a faulty vehicle speed sensor, or something more involved like an internal transmission problem. It seems as though you have an extreme symptom of what is called 'hunting', where the trans keeps changing between gears and/or revs up while trying to do so.

I would say inspect the VSS for any damage, cracks, or leaks around it, and check the wiring to it as well. If all that seems ok, you might be looking at a trans issue. If you have a scanner you can tell for sure if the VSS is functioning properly or not. Otherwise, you'll be forced to do a teardown of the transmission to see what exactly is the problem. If it's slipping internally, you would obviously have some smoked clutches and other hard parts inside. This would normally require a complete overhaul.
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JuggaloCujo
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Joined: Mon Dec 31, 2012 1:04 am

Re: Chevrolet P30 HELP!!

Unread post by JuggaloCujo » Tue Jan 01, 2013 10:20 pm

So the fuel/oil pressure switch that shoots out 4 drops of oil per second wouldn't affect the transmission?

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ProTech
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Re: Chevrolet P30 HELP!!

Unread post by ProTech » Tue Jan 01, 2013 10:22 pm

No, not at all...why would it? Have you ever seen an oil leak make the transmission shift all funky?! Not me...
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In the automotive industry for 20+

JuggaloCujo
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Re: 1996 Chevrolet P30 oil leak and transmission problem

Unread post by JuggaloCujo » Wed Jan 02, 2013 1:48 am

No, I have not but that oil leak is shooting directly into an electrical connector and leaking all over the transmission. I don't know where that electrical connector goes or what it's exact function is but I'm pretty sure that the transmission get's it's shift points from the engine and I'm also pretty sure that oil is not the best conductor. So I'm thinking that that particular electrical connection being interfered with could be causing the monkey business going on in the transmission. Given the fact that the transmission shifts perfectly fine up until it gets to 45-50mph I'm thinking it is NOT a mechanical issue that I am trying to find. However, I have no idea what a VSS is.

JuggaloCujo
Posts: 5
Joined: Mon Dec 31, 2012 1:04 am

Re: 1996 Chevrolet P30 oil leak and transmission problem

Unread post by JuggaloCujo » Wed Jan 02, 2013 1:49 am

Where is the vehicle speed sensor located? I can check into it's condition tomorrow....

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ProTech
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Re: 1996 Chevrolet P30 oil leak and transmission problem

Unread post by ProTech » Wed Jan 02, 2013 10:34 am

There you go thinking again!

OK, you say the oil leak is from the oil pressure switch right? Even if that's dumping a quart of oil a minute, it should NOT affect any transmission function! Now, you say you can't see where the oil is going? That's another story. If, perhaps the oil is leaking down the back of the engine or transmission and straight into the transmission electrical connector, then sure, you could have a problem. I've never actually seen that happen so I'm really doubting that is the cause. Get your oil leak fixed and then have the trans checked out. Just because a problem doesn't happen until a certain speed, does not mean there is not something wrong inside the trans....

And the VSS is the vehicle speed sensor, it's located in the rear of the transmission extension housing.
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In the automotive industry for 20+

JuggaloCujo
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Joined: Mon Dec 31, 2012 1:04 am

Re: 1996 Chevrolet P30 oil leak and transmission problem

Unread post by JuggaloCujo » Wed Jan 02, 2013 12:12 pm

I will get that switch replaced asap, and check the vss and I will take it to my brothers shop and have it scanned. I will keep you posted.

faisal
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Joined: Mon Sep 22, 2014 11:26 pm

Re: 1996 Chevrolet P30 oil leak and transmission problem

Unread post by faisal » Mon Sep 22, 2014 11:29 pm

No, not at all...why would it? Have you ever seen an oil leak make the transmission shift all funky?! Not me...


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