90gmcsierraL59
I'm Awesome
Greetings to all!
I am the proud owner of a 1990 GMC Sierra Shortbed Stepside that I bought in 2004 with 99000 miles. For another week it will have the factory 350 and 4l60 with 3.42 gears, single pull differential, automatic with AC, tilt and cruise. It is black with gray interior and cloth bench seat. 19 years later it still runs great, albeit down a bit on power. I use it occasionally for my 122 mile a day round trip commute to Dulles VA for my job. And I tow my 3 rail motorcycle trailer with it for my annual pilgrimage to East Tennessee to ride the Tail of The Dragon at Deals Gap. I run Amsoil 10W40 high zinc oil and a K&N oil filter and Dexron 6 synthetic in the transmission which was rebuilt at 220K after it lost drive and reverse on the way to work. I use Lucas 80/90 in the differential. The truck now has 240K on it and the motor uses very little oil. It carries 40 lbs of oil pressure at speed and between 20 and 25 pounds at a hot idle. The motor had a blown head gaket at 200K and was repaired, been fine ever since. Gas mileage is about 15 MPG at highway speed unladen and as low as 9 towing 3 bikes with a bed and cab full of stuff.
I am 65 and I decided that I want to keep this truck rather than buy a newer one so it is time to modernize it. I bought a donor 2004 LM7 5.3 and 4L60E with 104 K out of a wrecked Suburban for the swap and enlisted a dear friend in Raleigh NC to do it as the computer and wiring knowledge required is well beyond my old school capabilities. My friend does these swaps for a hobby and is a computer guy by trade as well as being a brilliant welder and fabricator. I will be taking the truck to him on the 27th and the fun will begin. We are using Dirty Dingo mounts and AC relocation bracket to retain the stock AC compressor to avoid notching the frame. A new knock harness and water pump are on the way along with a new transmission filter. The motor and transmission came complete with the harness and computer and the fly by wire accelerator pedal and harness. We will be running an X-pipe and true duals and the correct AC Delco high pressure fuel pump with steel braided lines and AN fittings. Motor will remain stock and retain the stock exhaust manifolds. We are running a Dakota Digital instrument cluster with blue back lighting in carbon fiber gray. The computer will be sent to a local company to delete the unused systems and we are still deciding on an 87 or 89 octane tune. We hope for somewhere around 300 horsepower and hopefully better gas mileage than the 350. Power should be more than adequate as there is 2000 pounds difference in weight from my truck (3800) and the 04 Suburban (5800) and the free flowing dual exhaust. I look forward to gaining some knowledge from you all in this forum and thank you in advance for any help or advice.
Tim Steele in Front Royal, VA
I am the proud owner of a 1990 GMC Sierra Shortbed Stepside that I bought in 2004 with 99000 miles. For another week it will have the factory 350 and 4l60 with 3.42 gears, single pull differential, automatic with AC, tilt and cruise. It is black with gray interior and cloth bench seat. 19 years later it still runs great, albeit down a bit on power. I use it occasionally for my 122 mile a day round trip commute to Dulles VA for my job. And I tow my 3 rail motorcycle trailer with it for my annual pilgrimage to East Tennessee to ride the Tail of The Dragon at Deals Gap. I run Amsoil 10W40 high zinc oil and a K&N oil filter and Dexron 6 synthetic in the transmission which was rebuilt at 220K after it lost drive and reverse on the way to work. I use Lucas 80/90 in the differential. The truck now has 240K on it and the motor uses very little oil. It carries 40 lbs of oil pressure at speed and between 20 and 25 pounds at a hot idle. The motor had a blown head gaket at 200K and was repaired, been fine ever since. Gas mileage is about 15 MPG at highway speed unladen and as low as 9 towing 3 bikes with a bed and cab full of stuff.
I am 65 and I decided that I want to keep this truck rather than buy a newer one so it is time to modernize it. I bought a donor 2004 LM7 5.3 and 4L60E with 104 K out of a wrecked Suburban for the swap and enlisted a dear friend in Raleigh NC to do it as the computer and wiring knowledge required is well beyond my old school capabilities. My friend does these swaps for a hobby and is a computer guy by trade as well as being a brilliant welder and fabricator. I will be taking the truck to him on the 27th and the fun will begin. We are using Dirty Dingo mounts and AC relocation bracket to retain the stock AC compressor to avoid notching the frame. A new knock harness and water pump are on the way along with a new transmission filter. The motor and transmission came complete with the harness and computer and the fly by wire accelerator pedal and harness. We will be running an X-pipe and true duals and the correct AC Delco high pressure fuel pump with steel braided lines and AN fittings. Motor will remain stock and retain the stock exhaust manifolds. We are running a Dakota Digital instrument cluster with blue back lighting in carbon fiber gray. The computer will be sent to a local company to delete the unused systems and we are still deciding on an 87 or 89 octane tune. We hope for somewhere around 300 horsepower and hopefully better gas mileage than the 350. Power should be more than adequate as there is 2000 pounds difference in weight from my truck (3800) and the 04 Suburban (5800) and the free flowing dual exhaust. I look forward to gaining some knowledge from you all in this forum and thank you in advance for any help or advice.
Tim Steele in Front Royal, VA
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