Chevrolet s10 4.3

Hi Guys,
Some American differential covers are held down with smooth Pan headed bolts with a female Torx center. These are common in pickup bed and other chassis hold down fasteners like seats and seat belts. The reason?? These driving tool bits self-center for the robotic and even fast human guided assembly in manufacturing.
The good news these are a hardened bolt so impact shocking works better than a soft bolt in a soft metal casting. Soft and soft will metals marry gladly to each other.

For the female Torx just like an Allen headed cap screw take a narrow flat nosed punch tip just fits inside the tool bit opening. Hit the punch HARD with a steel hammer. Several times. You are telling the bolts shank that it must let go of the housing threads. You are also slightly stretching the cap screws head from the blots shank relieving the clamping pressure.
Still the center Torx gripping edges flutes even after pick cleaned out often give up breaking and smoothing.
Then go to the outer edge of the round pan head with sharp chisel at an angle in the direction of spin out removal and cut raise up a metal lip-curl. This can usually start the cap screw rotating. If not; then switch back to the flat nose punch; hammer tapping the curl-step also in the direction of spin out. Sometimes you may have to make chisel cut edge steps in more than one location.
Sure, spray on your favorite penetrant between your mechanical massaging steps.

This same technique will work for true hex headed bolts too. The trick being to use a hammering shocking flat nosed punch as small as the guessed true unthreaded bolt shank diameter.
And this is the real trick for stubborn Phillips and cross-slotted screw fasteners! Leave enough of the original slots undistorted to be able to tap-tap reform these with your removal bit.

Truely it is the male headed Torx bolts that are the real stuck fast challenge. After hammer shocking you may not have anything left to grip. Grrr! Those the ones you end up grinding and drilling off their heads. Cursing the whole time.
Steve Unruh

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Whats the saying?—all it takes is 1 bolt to turn a 1 hr job into a 3 day job

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Tried changing the cover on the rear axle yesterday, it went very well, thanks for all the good advice.
The oil was very black, do you know if there is some kind of diff in these cars, or can I have 2 liters of 80-90 oil in the axle?

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In your S10? 80w90, do not add friction modifiers.

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Yes, in the s10, thanks Cody.
Was worried that there was some kind of diff on this one.

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Hi Jan, my s10 had a diff lock, (lamelldiff) then it needs LS classed oil (Limited Slip).
You didn’t snap a pic under the cover?
LS oil are not much more expensive at Biltema, and no danger to put it in ordinary differential.
(Often those friction discs tend to color the oil black).
LS oil use to mean there is no friction modifiers/improvers added, as Cody said.

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No, didn’t take a picture, but it looked different, maybe should change the oil again, before I drive more?

It shouldnt hurt the differential lock, it only slips easier, a friend with a Camaro drove about a year with wrong oil, complaining it keept spinning one wheel, i persuade him to change to ls oil, and it worked perfectly, and that was 350hp…

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The limited slip should be labelled as PosiTrac.

Check your VIN with a lookup to see if your truck was fitted with either standard or PosiTrac.

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I believe if memory serves correctly the option available with the s10 was a “govlock” differential which i have seen many running 80-90wt with no issues

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I tried with wine the number, but found nothing of the rear axel
1gcdt14w6sk122494
Edit: Loks like sae 80-90gl5 in the manual.

Just throwing this out for FYI certain years of the S10 had a sticker on the door of the glove box that when you found the code it would tell you just about everything about the vehicle including gear ratios.

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You mean the LPO codes? Should be there in the door jamb or in the glovebox on a sticker.

I went out and checked the intake, this is what it looks like after about 550 km.
I only have 7cm thick foam rubber as a filter, there is more soot than in the Illern anyway.

After clening.

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Jan, that looks about normal to me. Your soot looks more white, but that’s probably the camera flash.

In my case, the Volvo wollen blanket bag worked perfectly to begin with, but after a while more soot started to slip through. My theory is that small amounts of tary fumes over time made all the fluffy hairs stick together, leaving more open gaps.

Speaking of tar, I’ve noticed a sticky throttle every now and then. Especially ever since I put the new larger brake disc restriction in last summer. I have two throttle bodies and switch between them whenever needed. The one on the shelf I rip butterfy and shaft out of, clean with acetone and lube with grease.

Only a few weeks back I found a ss cone (6"- 8"dia). I installed it to raise the restriction and make the oxidation zone smaller, to see if the hesitation sympthomes would go away (they did not). The restriction now sits midways, on top of the cone, 7 inches below the nozzles and 7 inches above the grate.
However, with an hourglass shaped charbed the amount of char is smaller and as a result I reach normal gas temp outof the gasifier faster and the sticky throttle sympthomes are gone (for now). I haven’t yet been on a long enough trip to have the gasifier properly warmed through and see if the “open road level-off temp” increased as well.

Rambling on for no reason…

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Ok, the soot in mine is pretty dry, suck it out with the vacuum cleaner, think I get soot that goes past the foam rubber and the barrel, it doesn’t get really tight around the edge.
I have had about 3-4" resistance in the filter these 19 days I tried, no change in that time.
What kind of resistance do you have through your unit at 2000rpm?
Does the car hesitate when applying the gas, or how does it work?
Göran, did you have any soot at all when you used fiberglass?

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Sounds like a good enough reason to me. I like your rambles.

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How far do you have to drive to get to normal operating temps?
Bob

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Hi Jan, in the beginning there was almost no soot in the intake, very small amounts, i think it’s impossible to keep intake totally clean cause there is carbon released due to pressure drop.
Anyway the soot was thin like a coating of spray-paint, very dry. As glass-fibre stretches and wear along use there slips some soot but no problems.
Im going to post some pic’s of my intake when i disassemble it for cleaning soon, as i said my filter broke and i just keept driving for a long period, letting the cooler-bubbler catch the most soot, but it’s probably really dirty in the intake by now.

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At 2000rpm, full throttle and an ok charbed I may pull 12-15 inches on the rails. I never checked the Volvo’s filter resistance, but it’s probably higher than the big Mazda barrel, which shaves off only 1/6 of the total vacuum.

It seems I make equally potent gas at both idle and full bore. Accellerating hard from a standstill I have full power 1st and 2nd gear using the stored gas, but by the time “accelleration-gas” enters the motor it bogs down for maybe 5 seconds before it starts to recover. Annoying, especially if you have company, the accelleration is uphill and you’re in a hurry to reach your destination to utilize the restroom facilities. But on level road, no traffic, you’re in a calm state and accellerating gently, the hesitation isn’t noticeable.
A high idle, reving the engine or richening the mixture while sitting is not enough to overcome the problem. Richening while accellerating does help some though, and if there’s traffic behind with dual exhaust pipes for no reason, that can’t wait to stop at the next redlight, I just give the fuel switch a click or two.

It’s a matter of defenition. If I drive our small road into town (10-12 miles) and rarely exceed 50mph I would say I just about level off at 400F leaving the heatex when I get there. If I were to continue putter around at the same pace I wouldn’t expect the temp to climb much further = normal operating temp.
If I decide to continue my journey at 60 mph, in open road conditions, it would probably take me another 10 miles to level off at 500F = normal operating temp. At this state the gasifier is properly warmed through and the outgoing gas temp doesn’t fall below 400F, even at an idle. Keep in mind the trunk is really warm and cozy by now and my probe sits inside - on top of the heatex. No windchill factor :smile:

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