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Doug_Scott last won the day on January 17 2018

Doug_Scott had the most liked content!

About Doug_Scott

  • Birthday 04/11/1959

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  • Name
    Doug Scott
  • Location
    Ajax, ON
  • Gender
  • Drives
    2010 GMC SL Ext Cab 4.8

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  1. I would suggest contacting Precision Transmission. They have a YouTube site with more pertinent performance transmission information than any other site I have seen. Something you need to keep in mind is your transmission has a lockup converter in it that removes high stall speed once the convertor locks up. I'm from the old school when lockup converters didn't exist, actually Chrysler went to 727 and 904 with very basic lockups(compared to current offerings) in the late 70s, so driving with a high stall converter was something that was active at all times. Superchargers create torque with little to no delay. No real need for higher stall speed. If you are planning on needing a stall speed over 2500 and plan on driving your truck daily in a hilly terrain at highway speeds, you may find the transmission having to downshift or unlock the converter on hills. Prior to lockup converters it was a far simpler process of going to a higher stall speed.
  2. If you have broken metal parts due to timing belt/chain breakage you will have to locate the broken parts. Typically as Black02Silverado said, interferance engines require complete disassembly if cam timing is lost to the point of breakage.
  3. Between the title and the description I find it near impossible to figure out the question. At first I thought he changed his battery while the truck was running, not the smartest thing to do, and damaged the horn relay. But then after reading the story I thought maybe this was as simple as stale fuel setting off the sensor and all he needed to do was disable the sensor until he was sure the old fuel was burnt off. Then Jsdirt brings up aftermarket alarm system issues, so who knows now. I am near Toronto in Canada, if you want to flog it off cheap, let me know.
  4. The more I read my original post the more I think I have it backwards. The compensating port is for the disk brakes, not the drum brakes. The drum brakes use a residual check valve to maintain light pressure on the cups inside the wheel cylinders, and that valve also will prevent the line pressure from building from heat. Does loosening either caliper bleeder screw resolve the issue right away? A quick temporary test is to remove master cylinder from booster (do not loosen lines) and place two flat washers between the booster and the master cylinder. This will space the master away from the booster by the thickness of those two washers. Take truck for drive and see if problem goes away. If it does, then either the master has a plugged or blocked port on the front brake section not allowing the brake fluid to expand into the reservoir as it gets hot, or the connecting rod between the brake pedal and the piston in the master cylinder is too long. Given the age of the truck, take a good look at the firewall where the brake booster mounts for excessive rust or any cracking.
  5. Also try putting shifter into neutral and see it if will crank as well. The most common thing is bad battery cable connection. Do not just look at the connection and think it looks clean, take both cables off the battery, negative cable first, clean terminals and posts. Look carefully where wire enters terminal for any swelling or white powder. Do the same for the other end of both cables, making sure there is no bulging or white powder at end of wire. When re-connecting cables, connect negative last on battery.
  6. I went from 3.23 to 4.10. Only issue was speedometer and odometer. This was 11 years ago on my 2010. Jason at Blackbear fixed my speedo via the tune. Drove it for a couple of months before the tune and had zero issues with drivability.
  7. Go to youtube ( https://www.youtube.com/channel/UCYAAY7V9ifGS7Q8S35EFVnw ) and watch the videos by Precision Transmissions. Best place to find information regarding GM lockup issues. They are located in Amarillo, Texas.
  8. I would suggest putting the wallet away and start looking for the break in the "Engine oil pressure control circuit". Typically engine sensors have 3 wires, one ground, one power and one signal. Follow the wires back from the sensor and check every connection they go through. Most likely a bad/dirty connection at one of the harness plugs.
  9. You first need to check what type of light system you have. If they are LED you can rule out bulbs by tapping on the bulb. The other types of lighting systems will have filaments which can flicker easily. If your truck is under warranty stop trying to fix it yourself, let the dealer waste the cash. Assuming you live in the northern hemisphere it is still dark enough at 5pm to show dealer how to reproduce it. Depending on opening time they may also have some time in morning. You will have to get this reported before your sunlight time gets to the point you don't have time to show the dealer. This likely didn't start last week.
  10. Looking at MyCar website it appears to be a 3rd party device that adds some features that may or may not be part of the vehicle's factory devices. Not sure why all the "big brother hysteria" though. It has a simple plug-in connector and is out in the open so that it can be seen easily. Looks like there is zero effort applied to hide it. The MyCar website has enough information for you to figure out how to use it for whatever is not already part of the OEM equipment. If you were to contact the dealership that installed it, you could find out what the advantage is for the buying customer. It may simply be a way for the credit company to keep tabs on THEIR vehicle. Purchasing a near $100k (in Canada) vehicle with cash is hardly the norm for new vehicle purchasers.
  11. That is the exhaust manifold. A common issue that will not have an effect on the fuel management/engine roughness. If you are hearing an exhaust leak you will want to have it repaired. This is not an easy (as in skill level) task unless the broken bolt has enough of itself sticking out of the head to allow you to use a stud extractor tool to get it out. The task ranges from being able to get the broken bolt out just by removing the exhaust manifold to having to remove the cylinder head and having a machine shop get the broken bolt out. If you cannot hear an exhaust leak, leave it as is.
  12. Just unbolt the master cylinder from the booster and pull the master cylinder forward enough that you can either see behind it, or can get a finger behind the master to see if it is wet inside the booster. The only times I have ever had to bleed brakes at the wheels is when there was a part replaced after one of the flex hoses, or there was a complete brake fluid change to get rid of the water laden brake fluid. Bench bleed the master before changing it, and leave the bleeder lines on (assuming they still supply a bleeder kit with master cylinders these days). Bleeding at the master after installing it is not done the same as the bleeding at the wheels. To bleed the master after installing it, do not pump the pedal, just loosen the lines, have someone press the brake pedal down and then hold the pedal down as you close off the lines. Once closed, wait 10 seconds and have the helper release the pedal. Wait another 10 seconds, then crack the lines loose about a half turn and have the helper push the pedal down slowly, making sure they don't pump the pedal. Close the lines as the fluid comes out, and have the helper release the pedal after you have tightened the lines. It should only require a couple of bleeds to get a good pedal.
  13. Did this just happen one morning, or has the truck been sitting for a long time and you have little to no historic information on it? All internal combustion engines need 3 things to run, fuel, spark, and compression. Check compression on engine. Check timing by putting engine at TDC on number 1 cylinder and check the timing marks on crankshaft. While you are turning the engine by hand, watch the ignition rotor and turn in one direction until the rotor moves, then rotate engine the other way until the rotor turns. How far did you turn the crank between those two points. This test is best done at TDC #1 cylinder so you can mark the timing marks at the point where the rotor stats to move. You say you put a new distributor in, did you mean a complete distributor, or just the cap and rotor? Take the rotor off and look at the underside of the rotor, if you see any black marks replace it.
  14. I have a friend that is a retired GM employee, he bought a 04 Sierra SLT Ext cab in late 03, dealer had the factory ordered truck in under 2 weeks(helps that we are 10 miles from Oshawa plant), his only warrantee claim was an o2 sensor that failed as he was going through a car wash. He also had his ignition key replaced because the plastic/rubbery part broke where the ring when through. Then came my truck, then he bought a 2012 SLT 4x4 4 door along with his son getting a 2012 SLE 4x4 ext cab. His son's truck had to have the leaf springs replaced due to one leaf breaking, outside of warranty. He used his 04 truck to tow an enclosed trailer for motorcycle track days. No warranty issues, and no transmission issues. My last 4 new cars where in the 2000 and onward era, they all needed front rotors before 20k. I live in the Canadian rust belt. It may help that both him and I are licensed auto mechanics(we met working at a Chrysler dealership nearly 40 years ago). I get what you are saying about the stuff you see every day. You have to remember that you don't see the cars that don't have issues, and I will guarantee there are millions more that you don't see. Your reasoning was exactly the reason I bought a new Mustang in 78 while working at a Plymouth/Chrysler dealership as a transmission mechanic, every Plymouth I saw was broken, never saw a good one.
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