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Sudden really low oil pressure in my 365

  
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Sudden really low oil pressure in my 365

 
69GTOby 69GTOby
Guru | Posts: 1118 | Joined: 02/09
Posted: 12/07/13
11:00 AM

In my 365, in my signature below, I recently incurred a severe oil pressure issue.  I have always used Valvoline VR-1 oil in this engine.  Usually, 3 qts 10W-30 and 3 qts 20W-50.  I have always had >60 psi during a cold start, and at hot idle in gear, ~20 psi.  That's the lowest it would ever be.  It would always shoot right up to 50 or 60 when I revved it or floored it driving.

I recently changed the oil, maybe a month ago.  I used 3 qts 10W-30 and 3 qts straight 50, still Valv VR-1.  The SAE 50 was on sale.  Anyway, the next time I started the car, I right away noticed less pressure.  It has been getting cold outside, so it should, if anything be higher.  It only made 50 psi during the cold start.  I thought 'hmmm, that's odd.'  When driving to work, after like 10 mins of driving, I got to a stop sign and the needle was at 0 psi!  When I held it to 1k rpm it would go to like 10 psi.

So, after work I pulled it in and changed the small crappy Fram filter and used a Prime Guard filter we had in stock.  We have never had problems with this brand.  Still, low OP.  Today, I went and got a full sized AC Delco filter and filled it with 10W-30 - still low OP.  I tried bleeding the line to my mech gauge.  I even pulled the line off the gauge, it just drips out, when revved up, it's just a steady small stream straight down.  When I tap the Sun Pro gauge, the needle jumps around a bit but still returns to where it was.  I removed the T fitting with the elec sender for the elec gauge, which doesn't work anyway, and just ran the line for the mech gauge right to the filter adapter.  Still, really low/no OP.  Even when I rev it up once it's a little warm, I only get like 30 psi at 3k rpm or so.

Is there anything else I can do with the engine still in the car?  There's no engine noise at all, and it still runs great.  Sometimes when it would sit for a while, I would get some valve train noise for a couple seconds once started, and it's not even doing that...  
****
1969 GTO resto in progress. '76 350+.060, #13 heads, 9.2:1 CR, Lunati cam, Edelbrock Performer, 750 Holley, HEI, Ram Air manifolds, 2 1/2" exhaust. TH400 trans w/shift kit and 2400 stall.  235/60/15 front, 275/60/15 rear on Rally II 15X7s.  GM 12 bolt posi with 3.73's.

shyrgfuh3 shyrgfuh3
Enthusiast | Posts: 496 | Joined: 11/13
Posted: 12/07/13
11:26 AM

hello 69ftoby

you'll get lots of ideas but a bit more info might help.


" Sometimes when it would sit for a while, I would get some valve train noise for a couple seconds once started, and it's not even doing that."


did you have this noise before you installed the straight 50 wt?

what was the oil pressure when this noise would occur?

dores it sound like a lifter noise?

is it only at idle and goes away as soom as rpm increases?

if you are at a lite when this occurs does it continue ticking until you accelerate or wil it tick for a few seconds then stop then start then stop completely when you accelerate?

how old are the lifters?

when did you adjust them last?

how far in from 0 lash did you turn the adj nut?

are they comp cams brand lifters?


xxxxx


I removed the T fitting with the elec sender for the elec gauge and just ran the line for the mech gauge right to the filter adapter.  Still, really low/no OP.  Even when I rev it up once it's a little warm, I only get like 30 psi at 3k rpm or so.



remove fitting, look to see that it is not partially clogged, make sure oil pressure gauge line is clear, remove line at gauge and put open end in pan, start car, if oil does not hurl out of the hose then remove distributor and checxk ends of oil pump drive shaft,

if it is good then drain oil in open pan,

look for ultra fine metal flake floating on top in the sunlight, tgis is aluminum.

drag a magnet thru tge bottom of the pan, any metal that sticks is steel.

if you have more than a hint of metal in oil i would rebuild the engine.

if you see no metal then remove oil pump, disassemble and look for a prob then install new mellings oil pump.



what brand pump do you have?

is it high pressure or std?

why are you mixing oil?

what is your average outdoor temp while driving right now?

if avg temp is less than around 65 degrees you need 10wt-30 unless your engine is old and worn out or runs hot in which case you need to fix the hot running condition.


Read more: http://forums.highperformancepontiac.com/70/9595638/drivetrain-upgrade/sudden-really-low-oil-pressure-in-my-365/#ixzz2moXx5jDI  

69GTOby 69GTOby
Guru | Posts: 1118 | Joined: 02/09
Posted: 12/07/13
12:15 PM

The ticking noise would only happen occasionally if it sat for weeks at a time.  It would happen right on start up and last only a couple seconds, that was it.  Once the OP came up to 60+, which it used to do just a month ago, there would be no noise at all.  I think this noise is/was normal.  When the oil would settle after sitting for a while, it would take a second to pump through the engine again...  I'm using a Lunati cam and Lunati flat hydraulic lifters.

I was mixing oil because Valv VR-1 is not available in 10W-40, which I thought would be best.  So, I used 3 qts 10W-30 and 3qts 20W-50 figuring it would end up with 15W-40 viscosity.  I used 3 qts of SAE 50 this last time just because it was on sale for 5 bucks a quart and it is usually like 6.50 a quart or so.  I didn't think it would hurt anything.  And, I used a small, cheap Fram filter because it was on sale for 2 bucks.  Last time I try to save a few dollars, literally, on oil or filters.  Whether it's related to the issue or not, it's a mistake.

I guess I'll pull the dist and look at the pump drive shaft.  If it looks good I guess I'll drain the oil.  
****
1969 GTO resto in progress. '76 350+.060, #13 heads, 9.2:1 CR, Lunati cam, Edelbrock Performer, 750 Holley, HEI, Ram Air manifolds, 2 1/2" exhaust. TH400 trans w/shift kit and 2400 stall.  235/60/15 front, 275/60/15 rear on Rally II 15X7s.  GM 12 bolt posi with 3.73's.

shyrgfuh3 shyrgfuh3
Enthusiast | Posts: 496 | Joined: 11/13
Posted: 12/07/13
12:38 PM

ok


thanks for the info but i still don't understand if it did this with the new oil or the old oil or both so unfortunately i can't help you much there.

also don't know how cold it was etc.

don't know if you have a high pressure pump...


when many old school engines/cars sit for a while they will commonly tick for a few seconds upon initial start up then stop until it is parked for a week or so again.

if it ticks every time it has been sitting for 24 hours or less the lifters are weak.


if your oil pressure goes to 0, your lifters will start ticking within around 3 seconds and will quickly get worse the longer the pressure remains at 0. since your lifters were not ticking when your oil pressure gauge said 0 and they only ticked once upon initial start up after sitting for a while then your oil pressure was never at 0 so your gauge is no good or your line might be partially plugged also your lifters are not leaking so they are good.

in other words, according to your info so far you probably do not have any type of oil pressure prob at all and simply need a new gauge or need to clear the line to the gauge.


mixing 10-30 with straight 50 basically gave you 30wt-40 not good if its cold out like i mentioned. if you use thick oil you can damage the pump and/or pump drive shaft.


if the pump shaft is good i would still pull the line off and see if is squirts a steady stream of oil.


trying a new gauge might be a good idea also before ripping the pan off.  

69GTOby 69GTOby
Guru | Posts: 1118 | Joined: 02/09
Posted: 12/07/13
01:33 PM

Icon Quoteshyrgfuh3:
ok


thanks for the info but i still don't understand if it did this with the new oil or the old oil or both so unfortunately i can't help you much there.

also don't know how cold it was etc.

don't know if you have a high pressure pump...


when many old school engines/cars sit for a while they will commonly tick for a few seconds upon initial start up then stop until it is parked for a week or so again.

if it ticks every time it has been sitting for 24 hours or less the lifters are weak.


if your oil pressure goes to 0, your lifters will start ticking within around 3 seconds and will quickly get worse the longer the pressure remains at 0. since your lifters were not ticking when your oil pressure gauge said 0 and they only ticked once upon initial start up after sitting for a while then your oil pressure was never at 0 so your gauge is no good or your line might be partially plugged also your lifters are not leaking so they are good.

in other words, according to your info so far you probably do not have any type of oil pressure prob at all and simply need a new gauge or need to clear the line to the gauge.


mixing 10-30 with straight 50 basically gave you 30wt-40 not good if its cold out like i mentioned. if you use thick oil you can damage the pump and/or pump drive shaft.


if the pump shaft is good i would still pull the line off and see if is squirts a steady stream of oil.


trying a new gauge might be a good idea also before ripping the pan off.


Sorry for being confusing, lol.

I have not had any low OP problem with this engine before.

I don't know if I have a high pressure or standard pump.  It is a "reman Jasper block" I bought off a guy.  I think he said it was high volume, but not sure.

"when many old school engines/cars sit for a while they will commonly tick for a few seconds upon initial start up then stop until it is parked for a week or so again."
^I have experienced this with this engine.

"if it ticks every time it has been sitting for 24 hours or less the lifters are weak."
^I have NOT experienced this with this engine.

"if your oil pressure goes to 0, your lifters will start ticking within around 3 seconds and will quickly get worse the longer the pressure remains at 0. since your lifters were not ticking when your oil pressure gauge said 0 and they only ticked once upon initial start up after sitting for a while then your oil pressure was never at 0 so your gauge is no good or your line might be partially plugged also your lifters are not leaking so they are good."
^Exactly.

I pulled the dist.  Shaft looks good.  I turned it with a screw driver and can feel the pulses of the pump as I turn it, which is good.

I drained the oil into a clear container and watched it drain out.  I did not observe anything wrong with the oil.  I stuck a small magnet in the drain plug hole and did not pick up anything.

I put in 4 1/2 qts of 10W-30 Valv VR-1.  Still no OP at idle on the gauge.  I revved it up to 4k, gauge read almost 80 psi.  Then, let it idle and it went to 0.  I held it at 2k, gauge read 20 psi.  Again, 0 at idle.

I took the line off the gauge.  At idle it just drips. I revved it up to 4k+, and it just drools down.  This does not make sense!  With the line hooked up, at 4k the gauge spiked to near 80, but with the line off at 4k it just drools which sure as hell doesn't look like 80 psi.  What the???  Confused  
****
1969 GTO resto in progress. '76 350+.060, #13 heads, 9.2:1 CR, Lunati cam, Edelbrock Performer, 750 Holley, HEI, Ram Air manifolds, 2 1/2" exhaust. TH400 trans w/shift kit and 2400 stall.  235/60/15 front, 275/60/15 rear on Rally II 15X7s.  GM 12 bolt posi with 3.73's.

shyrgfuh3 shyrgfuh3
Enthusiast | Posts: 496 | Joined: 11/13
Posted: 12/07/13
01:54 PM

ok,

no metal in oil, good

no engine noises, good

no strong stream of oil from gauge line, not good.

oil pump pulses, not good.

your oil pump is exactly that a pump. it is gear driven. gear driven pumps only "pulse" when they get air in them. it's hard to check them for pulsing by turning them by hand. if you connect it to a drill and it does not give a continuous steady resistance the oil pan must come off.

you have enough pressure that your engine will not get damaged, you need to check the fitting and line and do what ever it takes to get a steady stream of oil if you want your gauge to work properly and to insure you have sufficient pressure at idle.

once you have a steady stream of oil you still might have air bubbles in the line but your gauge will still read properly. i have no idea why this phenomenon occurs.

you can pull plug wire at coil.

remove the line at the gauge

hold it at dash level

turn engine over until oil fills line.

connect line.

i have no idea if this will help but it shouldn't hurt.


they do not make a high volume pump for a pontiac so it might be a high pressuse one.



how cold is it there?  

69GTOby 69GTOby
Guru | Posts: 1118 | Joined: 02/09
Posted: 12/07/13
02:32 PM

I pulled the line off at the oil filter adapter for an instant with the engine idling.  Oil rushed out, so I quickly reinstalled it.  I figured the line must be clogged since oil ran out of the adapter with it idling, but only drips from the other end of the line at the gauge.

I tried another line, pretty confident the old line was clogged.  With a known good line installed, it is the same.  I tried to bleed the new line.  With the engine idling, I pulled the line off, it was bone dry, then some oil came dripping out.  I revved it up and oil came out a little quicker than before, but it still didn't look like any substantial pressure.  I hooked it up anyway, letting oil drip from the threads until I snugged it up.

Frustrated, I went out and drove it.  It never went above 25 psi, even at 4k.  At idle, 0 psi, driving at 2k, maybe 10 psi.  Those readings can't be right.  There's no engine noise and it runs strong!  I guess it must be the gauge??  It's just a cheap Sun Pro gauge.  This is really weird though.  I guess I'll try a new gauge tomorrow and see what happens.  I'm running out of ideas.  
****
1969 GTO resto in progress. '76 350+.060, #13 heads, 9.2:1 CR, Lunati cam, Edelbrock Performer, 750 Holley, HEI, Ram Air manifolds, 2 1/2" exhaust. TH400 trans w/shift kit and 2400 stall.  235/60/15 front, 275/60/15 rear on Rally II 15X7s.  GM 12 bolt posi with 3.73's.

shyrgfuh3 shyrgfuh3
Enthusiast | Posts: 496 | Joined: 11/13
Posted: 12/07/13
03:04 PM

ok,

so yoiu did what i said sand now it is worse, i guess i wouldn't take my advice anymore, lol.


when you cut those lines it occasionally smushes the line closed or smushes some of the plastic over the end you just cut unless you use a razor blade. no matter what you need oil gushing out that line.

since the fitting gushes oil but the line does not then make sure the ends of the line are not clogged

if they are not clogged then you may be tightening the nut too much. the more you tighten the nut the tighter the brass compression fitting clamps down on the line closing it off.

it is also possible your line is smaller inside than some. this makes it easier for the compression fitting to plug it off when tightened.

the compression fitting should fit snugly over the line without needing to sand the line to fit.

can yiu take a cell phone photo of the enside of the line where it is cut. you can post it here or put it on flickr etc and post the flickr link here.

this is a bit bizarre as you say but the good thing hopefully, is that you do not have a pressure prob.

i had a loose fitting at my gauge on my 69z28 and the carpet was dark green and it puked about a quart of oil on the new carpet before i caught it because it blended in with the carpet and was on the passenger side where i never go so i know for a fact that it should readily spew oil out that hose since we know it spews out the fitting at the eng on your car.



i would not buy a new gauge until i had a gusher out the hose because your new gauge won't work properly until there is.

you just might need a new hose with a larger inside.


where did you get the spare hose?  

69GTOby 69GTOby
Guru | Posts: 1118 | Joined: 02/09
Posted: 12/07/13
03:32 PM

I have an oil pressure gauge and a manifold vac gauge next to each other under the dash.  I use copper line for the vac gauge as well.  The vac gauge works fine, so I simply removed the line from the vac gauge and attached it over to the OP gauge, and moved the other end from the carb down to the filter adapter.

I am stumped...  I have never had this problem before with mech gauges and sender lines.  I have the same set of gauges in my truck and they still work well.  Maybe I will take the gauge out of my truck and try it in my car tomorrow.  But, like you said, oil should be gushing from the end of the line, and it's not.

I still don't know for sure if there is sufficient oil coming right out of the adapter.  I assumed so, because it gushed out, but perhaps I need to go back and try that again.  In fact, I may have a gauge I can screw directly into the adapter down underneath.  That would eliminate the line and the gauge entirely.  
****
1969 GTO resto in progress. '76 350+.060, #13 heads, 9.2:1 CR, Lunati cam, Edelbrock Performer, 750 Holley, HEI, Ram Air manifolds, 2 1/2" exhaust. TH400 trans w/shift kit and 2400 stall.  235/60/15 front, 275/60/15 rear on Rally II 15X7s.  GM 12 bolt posi with 3.73's.

wayne712222 wayne712222
Moderator | Posts: 235 | Joined: 10/13
Posted: 12/07/13
03:55 PM

i bet the THICK engine oil  pushed the oil pressure bypass valve piston back hard enough  that it crushed the spring..

i have pulled out oil pressure bypass springs.. in 7 pieces...

with a speed handle.. or a medium large variable speed drill.. spin the pump and see how much pressure you can make...  

shyrgfuh3 shyrgfuh3
Enthusiast | Posts: 496 | Joined: 11/13
Posted: 12/07/13
04:07 PM

yes if it gushed out the adapter one would think that you have sufficient oil to gush out a 4 ft line if the line is clear.

if you put you finger over the adapter gently while its idling one would think it should squeeze oil out past your finger.

yes, great idea if you can out the gauge right on the adapter. might need an adapter to do that though.

hope your old lady doesn't see the mess on the floor, lol.


wayne ha a good possible cause if your oil pressure is in fact low but even 5 psi would be enough to force it put your gauge line.



why am i getting the feeling that it is around 60 degrees or less outside when you drive this thing with 30wt-40 oil in it?  

wayne712222 wayne712222
Moderator | Posts: 235 | Joined: 10/13
Posted: 12/07/13
06:58 PM

this has been a thought bouncing around my head for a while...

do you have the ability to make a block off plate for the oil filter adaptor???

so you can remove it and bolt on this plate..  with a gauge on the oil pump output passage.. without the bypass in the adaptor so you have blocked off all the engine oil galleys... you are working with just the oil pump and a few inches of passage..

found one

Pontiacoilremotefilterada Zpsa7975467

Pontiacoilfilteradaptor Zps9a204769




how hard would this be to make out of something a little thicker so you could use a stock gasket to seal it to the block and not leak for the 3 minutes of drill testing.. as you would not crank the engine..  

hint.. if you had a shut off valve and a hose that looped back to the other passage..you could dead head the pump for bypass valve pop off testing and max pressure. but then you could open the valve and see if the oil system has tight enough bearing clearances to restrict the oil to build pressure.. again with the drill..

and if you are worried about sending unfiltered oil directly to the mains.. study how the oil filter relief valve works in the oil filter adaptor..  Shocked

end edit.


spin the oil pump up using an power drill... see how much oil pressure the pump can create .................................  see where the pressure bypass opens...

this can be done in the motor... without dropping the pan...

the block off plate could be created in half an hour ...


this is how the bypass pressure is tested...

Oilpressurereliefvalvetester Zps869183af

Oilpumppumping Zpsd2a4094e

Oilpumpbuckettest Zpsd47e9cf9

Oilpumpdyno Zpsfb3d7a1f




harbor freight has a torque device... allows you to use a breaker bar as a digital torque wrench..  i wonder if you could rig your oil pump drive tools to allow this to be in the middle and if this has a min max type setting.. so you could spin the drill till you got the oil pump bypass to pop off .. and see how much torque it took to do so...

Image 10461


the problem i see without blocking off the oil pressure adaptor... is you cannot block off the flow to build max pressure inside the pump..  so if the bearing clearances are opened way up because of the lack of pressure.. the flow will be tremendous.. and you cannot build pressure..

sorry i cannot seem to get out what i mean...

i know that here in los angeles there is an oil pump rebuilder.. they have an oil pump dyno.. they actually test oil pumps for engine rebuilders.. when there is an engine warrantee issue..  

they can chart oil flow by RPMs
they can chart torque required..
they can chart pop off pressure..


next time i am down in that area of los angeles.. i will stop in and ask them if i can snap a few images or perhap take a video of the oil pump dyno run..


in the mean time.. i really worry about you driving your car...  ZERO pressure is not enough to float the crank and cam on the bearing surfaces... you are going to get to the point where the bearing surfaces melt and weld to the crank journal and spin in their housing or big end bore.. at that point you are going to be in deep trouble..


an Oil pump that came loose on the block can also create this issue.. as can a pump that blew out the mounting gasket..

lets see.. if you install the plate above.. you are only testing the oil pump as i describe..  exactly...

Pontiac Oil Flow V8 Zps94a68dc4

and if that does not work.. just stuff in some high compression pistons..

Bigdommedpiston Zps574db02d

sorry.. i could not resist..  Laugh

hmm... just had a thought.. i could pick up some of these pistons.. a few bottles of diet soda and some mentos.. visit the battleship iowa .. see if i could get into one of the big guns and have some fun..  wwwooooosssssshhhhhh...


oh.. and here an oil filter bypass that is talked about below...

Pontiacoifliterbypass61temptest Zps5be16775

wow... that would be easy with a vertical mill.. to make out of aluminum  or even steel.. with a ball end drill to create a slot of the oil to travel from opening to opening..  

69GTOby 69GTOby
Guru | Posts: 1118 | Joined: 02/09
Posted: 12/08/13
11:44 AM

"i bet the THICK engine oil  pushed the oil pressure bypass valve piston back hard enough  that it crushed the spring..

i have pulled out oil pressure bypass springs.. in 7 pieces..."

Yes, this issue began right after I changed the oil with oil that is way too thick.  One mistake I will not be making again.  Is this the spring inside the adapter with the check ball?  I have another adapter I could try.

"with a speed handle.. or a medium large variable speed drill.. spin the pump and see how much pressure you can make..."

I figure I pretty much already did this with the engine spinning the pump, and it was insufficient press.

I love the idea of making a tool to test the oil pump.  This is something that would often come in handy.  The first image will not load on my screen for some reason.  It just shows a little icon in its place indicating an image was supposed to load there.  But, I can picture what you're describing.  You could use it to test the oil pump output, and then the pressure loss once allowed to pump through the galleys.  On an engine with some mileage, you could tell whether an OP issue was due to a worn out pump or to some pressure loss in the system from excessive bearing clearances or what have you.  Maybe an adapter could be rigged to serve this purpose as a diagnostic tool?  
****
1969 GTO resto in progress. '76 350+.060, #13 heads, 9.2:1 CR, Lunati cam, Edelbrock Performer, 750 Holley, HEI, Ram Air manifolds, 2 1/2" exhaust. TH400 trans w/shift kit and 2400 stall.  235/60/15 front, 275/60/15 rear on Rally II 15X7s.  GM 12 bolt posi with 3.73's.

shyrgfuh3 shyrgfuh3
Enthusiast | Posts: 496 | Joined: 11/13
Posted: 12/08/13
12:02 PM

"Yes, this issue began right after I changed the oil with oil that is way too thick."



Again, your oil is not WAY too thick unless you have snow on the ground. your oil is not even as thick a straight 40 weight so this theoretically should not have caused any prob but...

i think the factory spec for your car is straight 30wt so 30w-40 is not a huge jump. i have run far thicker than that with no problems.


xxxxx


"Is this the spring inside the adapter with the check ball?  I have another adapter I could try."



that won't hurt but there is another in the pump itself.


xxxxx



"I figure I pretty much already did this with the engine spinning the pump, and it was insufficient press."



how do you know it was insufficient pressure when oil gushes out the adapter and your engine can sit for more than 3 seconds without the lifters making any noise and the crank doesn't seize and there is 0 metal in your oil?

we already know your gauge is inaccurate because no oil comes out the line when it is disconnected sat the gauge with the engine running.


xxxxx


"I love the idea of making a tool to test the oil pump."



the easiest, cheapest, fastest way to test the pump is by simply looking at a properly working oil gauge.

did you try to connect your other one directly to the adapter?  

69GTOby 69GTOby
Guru | Posts: 1118 | Joined: 02/09
Posted: 12/08/13
01:00 PM

Well, I live in MD, and yes, there is currently a half a foot of snow on the ground, LOL.  First snow fall of the year.  I have only run the car in the 40's (*F).

When you mix oil viscosity, does it really work out that the average viscosity is what you end up with?  (3 qts 10/30 + 3 qts 20/50 = 15/40)  Does it really work like that?  

If that's the case, as we established, I effectively had 30W-40 in there, which admittedly is probably too thick for the winter.  But, before they had multi viscosity oil, many were likely running SAE 30 in the winter, and I assume they didn't break anything in doing so.  I am wondering if my SAE 50, although it was mixed in with 10W-30, maybe was just too thick and didn't really mix with the thinner stuff, and the pump tried to push SAE 50 thru the engine and adapter and something broke.  I can't see 30 weight oil breaking something, but I could see straight 50 breaking something in the cold.  You know what I mean?

So, as of now, it seems that either I am not getting an accurate reading, and the engine actually has sufficient press, OR, I really do have low press because my SAE 50 was too think and it broke a press relief spring in either the oil pump and/or the adapter.

I won't know for sure until I keep delving into it.  It is frustrating and bizarre that after all I've done I still don't have my answer, but that's just the way it goes sometimes.  Right now, the car is out in the snow, which SUCKS.  The poor thing has to sit out in that stuff because I don't have a garage to put it in!  
****
1969 GTO resto in progress. '76 350+.060, #13 heads, 9.2:1 CR, Lunati cam, Edelbrock Performer, 750 Holley, HEI, Ram Air manifolds, 2 1/2" exhaust. TH400 trans w/shift kit and 2400 stall.  235/60/15 front, 275/60/15 rear on Rally II 15X7s.  GM 12 bolt posi with 3.73's.

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