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What did you do with your GMT400 today...or yesterday....

Not quite finished but running. Have a little drip at the quick connect heater hose and need to drain water and put coolant in it (rinsing it out on start up with just water). I just finished: New HO water pump, Duramax fan and new fan clutch, timing gears, Fluidamper harmonic balancer, Leroy's solid crank pulley, engergy suspension engine and transmission mounts. What a PITA to do drivers side engine mount with 4x4.

Did the Energy Suspension engine mounts make a difference? Is there a trick to getting them in?
 
The poly in the clamshells was easy. I drilled out the crimp. I pinched the shells down in a vice andI used some 1/4” bolts to hold them together. The shells have a almost corregation to them that nests between each other to lock orientation together once all screwed down. The way they were the screw heads did not interfere with them laying flat.

The PITA is getting the clamshells out from under engine above the differential, oil cooler hoses, drive shaft, and my remote filter hoses.
Drivers side is just tight.
 
As far as the Energy Suspension mounts making a difference. I say yes they do. My OE ones were toast at ~ 20 years 262K miles and allowed the engine to shake a bit if you roamed on it coming back to idle. They caused some clutch launch shudder too.

I also installed the plastic Duramax fan it's a little bigger and not much room to clear the shroud. I used a 4-1/2 inch grinder with a sandpaper disc to trim back the shroud just to give the fan a little more clearance. My old tired engine mounts the fan would have rubbed when the engine torqued on the mounts and think the energy suspension mounts are a good combo to the larger fan and keeping it from hitting the fan/radiator shroud.
 
last weekend i removed the ATT and put in the GMX from the 96. homemade TM gives me 10 at 75 mph, 8 at part throttle and 4 on cruise at 65. best the ATT gave me was 2 at full throttle.

2 weeks ago i picked up this 100 gallon aluminum tank. it has a sending unit so i'll get the correct ohm piece and connect it to the OEM gauge. got it for 50 dollars. i'll be putting it in after i build some brackets. it will be replacing the 30 gallon i have in there now.
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last weekend i removed the ATT and put in the GMX from the 96. homemade TM gives me 10 at 75 mph, 8 at part throttle and 4 on cruise at 65. best the ATT gave me was 2 at full throttle.

2 weeks ago i picked up this 100 gallon aluminum tank. it has a sending unit so i'll get the correct ohm piece and connect it to the OEM gauge. got it for 50 dollars. i'll be putting it in after i build some brackets. it will be replacing the 30 gallon i have in there now.
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Do you feel a big difference in power going from the ATT to the gmx?

Are you selling the ATT or keeping it?

Wonder why you only got 2 lbs at full throttle with it?
 
Noticed after replacing the shocks on the burb that the squeaking didn't go away. They had almost 300k on them, they had to be done. After some investigation the squeak is coming from the lower control arm rear bushing. When the bypass oil lines blew last year I guess I didn't clean it off good enough because I got oil all over my hand feeling around it. That one is a PITA. I just did it 2 years ago. 😭 Anyone have any tricks to get it without taking everything everything apart from the calipers, ball joints, rotors, etc.?
 
Noticed after replacing the shocks on the burb that the squeaking didn't go away. They had almost 300k on them, they had to be done. After some investigation the squeak is coming from the lower control arm rear bushing. When the bypass oil lines blew last year I guess I didn't clean it off good enough because I got oil all over my hand feeling around it. That one is a PITA. I just did it 2 years ago. 😭 Anyone have any tricks to get it without taking everything everything apart from the calipers, ball joints, rotors, etc.?
Drive to the mechanic shop near a good restaurant. Bring a credit card for both places...

Nope. It has to come out for it. If only there was a way.

Hummers use upper and lower a arms in front and back axles. All 16 new bushings are on the shelf waiting for me to tackle once the engine is built, and for me to take some serious pain killers before starting- haha. Doing all upper and lower ball joints, shocks at same time. Maybe new front springs too if I find a good price on some.
I feel your pain. Press them out vs burning them out is always the question, harbor freight sells an ok press cheap...
 
After a new coolant pump install, then driving the truck through several heat/cool down cycles, I happen to glance under the front, prestone on the ground. I was about ready to cry and just give up. after inspecting the camper, I popped open the hood. bypass hose had a seep, went to the garage, got the 5/16ths socket and 1/4 ratchet combo, went out and snugged the clamps, no more seepage. I guess My hands is not as strong as they once were that a 1/4 nut driver and socket will give enough torque to make a lasting tight band and connection. LOL
 
Did some research on the various OEM senders and their circuitry since some of the OEM gauges are swinging around wonky like as well as the all the ISSPRO's going haywire (different grounds for the ISSPRO's). Biggest issue is the Coolant Temp gauge's needle is sitting on the bottom peg. Ungood!
Hard to clean grounds for the CTS as it is grounded to the engine by just being screwed in (like the OPS) so I went for the instrument panel's ground along with the PCM etc. (G104 and 105 on the right hand upper intake above 6 & 8). Additionally, I corrected the separate/stand alone ground for the OPS. I used a 45* XRP anodized fitting for the OPS/Turbo Oil Feed set up (509 block w/o dedicated OPS port under the...long story) and there's a rubber O-ring in the XRP fitting allowing it to swivel yet not leak. That's all well and good but, there's no direct path to ground for the OPS. Anyway, Re-did that with a 16 gauge Ring connector to ensure better contact than the one I had just cobbled up. Just have to drive the truck to see if the CTS circuit is healed or, I need to replace the CTS sender. The ISSPRO issue's will have to wait for another day.
From the 'while I was in there' department, I noticed some rust on the chrome valve covers and in cleaning that up the chrome started to flake off the passenger side unit. I believe it was Husker who WAY back during the build in 2013 called the fact that it might do that. Not making any 'he jinxed it" claims, just credit for a correct prognostication. The Run Cool Hood Vents give mother nature un-restricted access to the engine compartment so nothing stays clean in there anyway. "This is why we can't have nice things." Guess when I swap out the injectors, I'll just pull it all apart and put the other set of Valve covers on since there appears to be a slight leak on the driver' side and a little rust too. Of course, that's after I ensure the old set is level/true and, maybe, powder coated. Love/Hate this truck.
 
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Did some research on the various OEM senders and their circuitry since some of the OEM gauges are swinging around wonky like as well as the all the ISSPRO's going haywire (different grounds for the ISSPRO's). Biggest issue is the Coolant Temp gauge's needle is sitting on the bottom peg. Ungood!
Hard to clean grounds for the CTS as it is grounded to the engine by just being screwed in (like the OPS) so I went for the instrument panel's ground along with the PCM etc. (G104 and 105 on the right hand upper intake above 6 & 8). Additionally, I corrected the separate/stand alone ground for the OPS. I used a 45* XRP anodized fitting for the OPS/Turbo Oil Feed set up (509 block w/o dedicated OPS port under the...long story) and there's a rubber O-ring in the XRP fitting allowing it to swivel yet not leak. That's all well and good but, there's no direct path to ground for the OPS. Anyway, Re-did that with a 16 gauge Ring connector to ensure better contact than the one I had just cobbled up. Just have to drive the truck to see if the CTS circuit is healed or, I need to replace the CTS sender.
From the 'while I was in there' department, I noticed some rust on the chrome valve covers and in cleaning that up the chrome started to flake off the passenger side unit. I believe it was Husker who WAY back during the build in 2013 called the fact that it might do that. Not making any 'he jinxed it" claims, just credit for a correct prognostication. The Run Cool Hood Vents give mother nature un-restricted access to the engine compartment so nothing stays clean in there anyway. "This is why we can't have nice things." Guess when I swap out the injectors, I'll just pull it all apart and put the other set of Valve covers on since there appears to be a slight leak on the driver' side and a little rust too. Of course, that's after I ensure the old set is level/true and, maybe, powder coated. Love/Hate this truck.

Did you get to replacing the steering column joint with the Twisted Steel version?

My wife is all torqued because the driver’s side passenger door won’t lock with the remote. So that actuator must be out. This is the door with that rust spot, so I have an entire door assembly, same color, in the waiting to install. I best get to it. Otherwise the truck has performed well. We’re headed south and intend to stay in Nephi tonight.
 
Did you get to replacing the steering column joint with the Twisted Steel version?

My wife is all torqued because the driver’s side passenger door won’t lock with the remote. So that actuator must be out. This is the door with that rust spot, so I have an entire door assembly, same color, in the waiting to install. I best get to it. Otherwise the truck has performed well. We’re headed south and intend to stay in Nephi tonight.
The ISSPRO Oil Pressure Sender isn't functioning either. It is installed in a port on the driver's side above the exhaust manifold so I'll need to pull the inner fender to address it so, 'while I'm in there' I'll get after the steering column joint. The door lock issue is more than likely gack build up on the actuator rods. Pop the door card and clean them with a scratch pad (especially around the plastic guides) and then lubricate with either silicon or Teflon spray. Give the door handle lock guides a little spray as well.
 
The ISSPRO Oil Pressure Sender isn't functioning either. It is installed in a port on the driver's side above the exhaust manifold so I'll need to pull the inner fender to address it so, 'while I'm in there' I'll get after the steering column joint. The door lock issue is more than likely gack build up on the actuator rods. Pop the door card and clean them with a scratch pad (especially around the plastic guides) and then lubricate with either silicon or Teflon spray. Give the door handle lock guides a little spray as well.

I don’t even hear the actuator trying to work against sticky rod. It’s dead.
 
Drove from Stevensville, MT to Nephi, UT for a total of 632 miles. Tomorrow Nephi to Fullerton CA, about 540 miles. ‘99 Suburban running great and will roll past 221K on the odometer early tomorrow. Probably about 2,500 for the trip. Speed limit is 80 most of the way.
 
I don’t even hear the actuator trying to work against sticky rod. It’s dead.
The door actuators on Mine truck all work relatively well, most the times. When the ambient air temps get into the 80s and the truck is setting out in the sunshine, it gets hot in the truck, then, some of the windows fail to function from any switch. RR window will go up and down as long as a switch for another window is depressed, LF front window does not function no matter what. LOL
 
Do you feel a big difference in power going from the ATT to the gmx?

Are you selling the ATT or keeping it?

Wonder why you only got 2 lbs at full throttle with it?
a LOT more power! it's like a new to me truck.

ATT is for sale. if interested, send me a private message and we'll discuss a trade or price.
a guy wanted it a year ago on the GMT400 site a year ago. sent him a message but no response yet. i procrastinated a whole year before i felt well enough to put it in.

my thought is the ATT likes it above 2K rpm and i never got it past that. with the gearvenders i never had the need. i pushed it to 70 because i wanted to see what it would max out to at the fastest speed i'll probably want to go.
 
Oh yeah- the ATT isn’t even spooling at 1700. Heck at 1300 I bet the blades dont turn -haha.

Thats part of why I think the ATT would be good for Hummers that do descent freeway time. They are cruising at 2500-2650 all day long. If it has a qsv then would be awesome for it.

No qsv means no low rpm boost (as you experienced) and it would kill power offroading when rock crawling, water crossing, etc

Fitting it with the qsv in the ultra tight hummer area is my biggest hang up with them.
 
a LOT more power! it's like a new to me truck.

ATT is for sale. if interested, send me a private message and we'll discuss a trade or price.
a guy wanted it a year ago on the GMT400 site a year ago. sent him a message but no response yet. i procrastinated a whole year before i felt well enough to put it in.

my thought is the ATT likes it above 2K rpm and i never got it past that. with the gearvenders i never had the need. i pushed it to 70 because i wanted to see what it would max out to at the fastest speed i'll probably want to go.

I can’t buy it I was just asking.

I forgot that you had the gear vendors. Makes since to me now that it didn’t work for you
 
Drive to the mechanic shop near a good restaurant. Bring a credit card for both places...

Nope. It has to come out for it. If only there was a way.

Hummers use upper and lower a arms in front and back axles. All 16 new bushings are on the shelf waiting for me to tackle once the engine is built, and for me to take some serious pain killers before starting- haha. Doing all upper and lower ball joints, shocks at same time. Maybe new front springs too if I find a good price on some.
I feel your pain. Press them out vs burning them out is always the question, harbor freight sells an ok press cheap...
I have a HF press that I used to do them 2 years ago. It was a pita. Never burnt them out before is it faster?
 
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