absolutely do not turn them back on. they have physical lock pins that keep the lifters from going into dod mode. oil releases the pins and if they get stuck. you now have a collapsed lifter to pull the head over
What did you do to your NNBS GMT900 Tahoe/Yukon Today?
- Thread starter phattyford
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absolutely do not turn them back on. they have physical lock pins that keep the lifters from going into dod mode. oil releases the pins and if they get stuck. you now have a collapsed lifter to pull the head over
lowh07
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I got the HX bearings installed. Plastigage looked good but I decided to get a micrometer and dial bore gauge since it's more than a basic rebuild. This is what I'm seeing and I think it looks pretty perfect.
1. .0030
2. .0029
3. .0029
4. .0031
5. .0031
Cleaned everything very well and got the crankshaft installed and torqued down. Spins really nice with zero binding. End play is looking like .005-.006 so I think that's also probably good. Hopefully it's in there for good! I won't know for sure until I can verify the clearance between the rod bolts and the bottom of the cylinders. Might need to do some clearancing for the 4" stroke. Going to gap the piston rings next.
Edit: Summit just confirmed I will not need to touch the block (other than lightly deburring the bottom of the cylinders which is already done). Happy!!!
1. .0030
2. .0029
3. .0029
4. .0031
5. .0031
Cleaned everything very well and got the crankshaft installed and torqued down. Spins really nice with zero binding. End play is looking like .005-.006 so I think that's also probably good. Hopefully it's in there for good! I won't know for sure until I can verify the clearance between the rod bolts and the bottom of the cylinders. Might need to do some clearancing for the 4" stroke. Going to gap the piston rings next.
Edit: Summit just confirmed I will not need to touch the block (other than lightly deburring the bottom of the cylinders which is already done). Happy!!!
Last edited:
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I got my boost gauge installed, nothing fancy, and its showing just my how much impact my conversion to 4.10 (versus 3.42) really made on performance. Without the boost gauge, I could not tell for sure how much impact the 4.10 gears had on performance versus the supercharger. Now, I can see that the impact of the 4.10 gears is very significant, since the truck accelerates much better, even before the boost kicks in.
I've got a long trip ahead of me, so I will be able to see how my highway mileage is impacted by the 4.10 gears.
I've got a long trip ahead of me, so I will be able to see how my highway mileage is impacted by the 4.10 gears.
Ordered this "kit" for the water hose connections and for the price they are actually pretty nice. Every bit as good as the Doorman pieces.
Only thing that kit is missing is spring clamps.
I toss ever spring clamp away i can when i get the chance on my vehicles, hate 'em! I try to use rolled edge clamps. Hard to find good one's but well worth the price.
Nice.
When I changed out mine to the metal connectors, I also did the hose to the water pump which also includes another plastic fitting near the pump, mainly for peace of mind.
This kit has that piece just without the hoses. It’s the one on the bottom right .
Ahh, copy...missed that.
That’s what I like about that kit. That part usually gets overlooked by most folks.
Found a couple parking sensors on the bay for about $80 delivered in white diamond tricoat..was in shock of the price of OE sensors which also need to be painted. They are in excellent shape and they are too small to see any possible variances in paint batches.
I'm sure aftermarket sensors are good, but still needs paint.
My broken one on right.
I'm sure aftermarket sensors are good, but still needs paint.
My broken one on right.
Mickey_7106
Full Access Member
Why I do random underbody inspections 02 sensor harness was melting on the exhaust caught it just in time, loosely zip tied it to the brake lines
Inside
Semi annual engine cleanup/degrease
I was under it again because I have been getting a clanking noise anytime I went over a bump or small pothole, thought it was my ghetto transmission cooler mount under the bumper but secured that up pretty good the other day and the clank was still there. kind of sounded like a loose brake caliper or something but I think I found the source. The rear sway bar upper end links. I believe the bushings have shrunk a tiny bit enough for the bolts to "rattle" so I tightened both of them up a bit and that seems to have resolved it, can't say for sure because there are no potholes of any size around the house. I tried to hit the ones I could find on a short drive and no more rattle/clank
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I'm back from my trip into the Berkshires and Adirondack mountains, and I got some good insight into my current 4.10 gears and supercharger setup.
My mileage with the 4.10 gears and supercharger was 15.3 mpg on the trip, and that compares to 17.1 mpg on a previous trip with 3.42 gears and the supercharger. BUT, the 2 trips were on different roads with different elevation maps, so my mpg findings may be a bit distorted. The first trip was on predominantly on reasonably level roads, and the most recent trip was on a significantly larger percentage of miles in the mountains. My feeling is that if both tests were on the SAME road, the difference in mpg between the 2 gear ratios would be substantially smaller.
Here is the most interesting insight that I got. With the 3.42 gears traveling through the mountains at 60-75 mph, I would get gear downshifts on the most upward inclined portions on the mountain roads. I'm not sure what the supercharger was doing, as I did not have a boost gauge at the time. With the 4.10 gears, I very rarely got a downshift on the most upward inclined portions on the mountain roads. What I did see, though, was that I got between 1.0 and 2.5 lbs. of boost from the supercharger, when going on the most upward inclined portions on the mountain roads, but still remaining in 6th gear. As such, my supercharger got much less work than I had anticipated on this trip. I will note that I used my cruise control on most of the trip.
On the trip home, it was in the 90's temperature-wise, and for the first time, I saw coolant temperatures go above 210 degrees, perhaps as high at 225 degrees on the most upward inclined portions on the mountain roads. If I turned off the AC, the coolant temperature would retreat back to 210 degrees. My question to the Forum Members is, can I upgrade my cooling fans to the 700 watt cooling fans as a direct plug and play upgrade? And, do I need a different wiring harness and connectors to achieve this upgrade?
My mileage with the 4.10 gears and supercharger was 15.3 mpg on the trip, and that compares to 17.1 mpg on a previous trip with 3.42 gears and the supercharger. BUT, the 2 trips were on different roads with different elevation maps, so my mpg findings may be a bit distorted. The first trip was on predominantly on reasonably level roads, and the most recent trip was on a significantly larger percentage of miles in the mountains. My feeling is that if both tests were on the SAME road, the difference in mpg between the 2 gear ratios would be substantially smaller.
Here is the most interesting insight that I got. With the 3.42 gears traveling through the mountains at 60-75 mph, I would get gear downshifts on the most upward inclined portions on the mountain roads. I'm not sure what the supercharger was doing, as I did not have a boost gauge at the time. With the 4.10 gears, I very rarely got a downshift on the most upward inclined portions on the mountain roads. What I did see, though, was that I got between 1.0 and 2.5 lbs. of boost from the supercharger, when going on the most upward inclined portions on the mountain roads, but still remaining in 6th gear. As such, my supercharger got much less work than I had anticipated on this trip. I will note that I used my cruise control on most of the trip.
On the trip home, it was in the 90's temperature-wise, and for the first time, I saw coolant temperatures go above 210 degrees, perhaps as high at 225 degrees on the most upward inclined portions on the mountain roads. If I turned off the AC, the coolant temperature would retreat back to 210 degrees. My question to the Forum Members is, can I upgrade my cooling fans to the 700 watt cooling fans as a direct plug and play upgrade? And, do I need a different wiring harness and connectors to achieve this upgrade?
the fans are 100% plug-n-play but I don't know how much help they will be, I would have to assume the intercooler is what drives the temp up.
you might do better with a front mounted forced air fan, that was my game plan if needed.
I am pretty sure on mine too that hollowing out that 3rd cat helped also with heat dissipation, it's not monitored in any way.
Before you go that route, some things to consider:
1) Does the ECU cut off the fans above a certain speed?
2) If the answer to #1 is "yes," was your speed above the cutoff speed?
3A) If the answer to #2 is "yes," then the higher-capacity fans wouldn't help by themselves.
3B) If the answer to #2 is "yes," changing the cutoff speed in tuning might do the trick by itself without the need for additional fan capacity.
