How long would you run these injectors?

[Bdsankey]

I plan on definitely running GM cleaner at least one more time, I still have 4.5 bottles of it. I’ll probably run the supply and return into two separate containers this time... it looked a dirty last time, but I suppose it looking dirty is a good thing?

I just grabbed all my tools and garage stuff from SoCal to move into my new house, once I get the trailer out of the driveway blocking my garage I’ll mess with the truck.

Just remember, when you're running it into one bucket you do have the fuel filter in place. The problem is you've got all this cleaner that doesn't get used if it is returned so you theoretically would need more fuel volume to do the same job. Like James said, if the GM cleaner didn't do the trick I wouldn't be using ATF. I've never seen ATF be beneficial and have noticed the same thing James has of accelerated increase in noise from the injectors.


Some people swear by using ATF, some by 2 stroke oil, some by used motor oil, some by fuel additive, and some use nothing etc. It's up to you, I am just giving my opinion. I've used 2 stroke oil (non-synthetic TCW3 certified) for ~10 years and haven't had any injector issues on vehicles I know the complete service history on or ones I've replaced the injectors/fuel system parts on. Now I use OptiLube XL in the summer and XDP/Winter or XL/Winter in the cold weather months.

 

[fl0w3n]

I’ve also been playing around with what wheels to go with, here’s my crack at some edits. They aren’t really to scale, but I’d like to do 17s and 35s with some massaging to the front to make it fit. Otherwise I’d go with 16s and 33s.

I’m leaning towards the 704 Titanium’s or 305s, the machined doesn’t look as good as I expected on the silver birch.

 

[fl0w3n]

Just remember, when you're running it into one bucket you do have the fuel filter in place. The problem is you've got all this cleaner that doesn't get used if it is returned so you theoretically would need more fuel volume to do the same job. Like James said, if the GM cleaner didn't do the trick I wouldn't be using ATF. I've never seen ATF be beneficial and have noticed the same thing James has of accelerated increase in noise from the injectors.


Some people swear by using ATF, some by 2 stroke oil, some by used motor oil, some by fuel additive, and some use nothing etc. It's up to you, I am just giving my opinion. I've used 2 stroke oil (non-synthetic TCW3 certified) for ~10 years and haven't had any injector issues on vehicles I know the complete service history on or ones I've replaced the injectors/fuel system parts on. Now I use OptiLube XL in the summer and XDP/Winter or XL/Winter in the cold weather months.

True, the fuel filter is in place, but whatever (assuming rust) was making it browner wasn't getting caught by the filter. I guess if it's not getting caught then it probably isn't causing problems by passing through the system?

I should order a couple extra filters. There was a NAPA Gold one on from when I bought it, but I just threw an AC Delco one on for fricken $70 from the dealer.

 

[DAVe3283]

I've run two stroke oil when the FPR starts getting sticky. Seems to help squeeze some life out of a FPR, bit never seen any other positive effects. Or negative effects, but I also run it from 1000:1 and increase up to 500:1 as the FPR keeps getting worse. Beyond 500:1 I never saw a benefit.

The steering column rattle at idle is that lower green bearing. But it might not be the upper steering shaft rattling in the bearing, it could be the bearing rattling in the column. That's what it was on my Suburban. New bearing didn't fix anything. What did the trick was get a high quality hose clamp, and clamp down on the column around the bearing. You can grab the steering shaft and wiggle it to see/hear the bearing flop around. I tightened the hose clamp until the bearing couldn't move around, but no tighter. Figured no need to hurt the thing, it's plastic after all. Been that way for years, no rattle since.

Sent from my ONEPLUS A6013 using Tapatalk

 

[Bdsankey]

True, the fuel filter is in place, but whatever (assuming rust) was making it browner wasn't getting caught by the filter. I guess if it's not getting caught then it probably isn't causing problems by passing through the system?

I should order a couple extra filters. There was a NAPA Gold one on from when I bought it, but I just threw an AC Delco one on for fricken $70 from the dealer.

You've also got to remember it's cleaning everything. What you're seeing is from the return side thus it's cleaning that as well.


GM TP3018 is $47.10 and the Parker/Racor (exact same filter as the TP3018) is $38.63, if the dealer charged you $70 that hurts unless it somehow came with the WIF sensor.

 

[fl0w3n]

I've run two stroke oil when the FPR starts getting sticky. Seems to help squeeze some life out of a FPR, bit never seen any other positive effects. Or negative effects, but I also run it from 1000:1 and increase up to 500:1 as the FPR keeps getting worse. Beyond 500:1 I never saw a benefit.

The steering column rattle at idle is that lower green bearing. But it might not be the upper steering shaft rattling in the bearing, it could be the bearing rattling in the column. That's what it was on my Suburban. New bearing didn't fix anything. What did the trick was get a high quality hose clamp, and clamp down on the column around the bearing. You can grab the steering shaft and wiggle it to see/hear the bearing flop around. I tightened the hose clamp until the bearing couldn't move around, but no tighter. Figured no need to hurt the thing, it's plastic after all. Been that way for years, no rattle since.

Sent from my ONEPLUS A6013 using Tapatalk

Thanks for clarifying. Now that you say that I remember reading about the hose clamp fix. It’s never been bad enough on past trucks to worry about, but this one sure is getting on my nerves.
I’ll check the play before I order the bearing.

You've also got to remember it's cleaning everything. What you're seeing is from the return side thus it's cleaning that as well.


GM TP3018 is $47.10 and the Parker/Racor (exact same filter as the TP3018) is $38.63, if the dealer charged you $70 that hurts unless it somehow came with the WIF sensor.

Good point, so it could even be getting discolored by passing through the junk that had been caught in the filter.

yeah, unfortunately I got raked on that one. Same day I was supposed to do a 3 hour out of town trip I realized I had forgotten to change the filter after the injector cleaning and I wanted to do it before the drive. I chose to get raked by the dealer vs risking a parts store knock off.

 

[fl0w3n]

This thread is kinda becoming my dumping place for questions about this truck... maybe once I actually collect some parts I'll make a "build" thread

I think this question is mostly for @Chevy1925 because I'm curious about spring rates on the torsion setup and shock choices, and you seem pretty knowledgable on suspension performance and specifically these trucks.

I badly need new shocks on this truck, but like always, I'm going through paralysis by analysis - which shock do I go with now? I dream of one day my budget opening wide up and being able to do the FOX DSC 2.5's and spring under deaver's out back... but for now, my budget is much less than that.

I'm leaning towards the FOX 2.0's all around, and later down the road maybe a deaver mini pack and a re-arch on the main pack to buy time. The only thing I'm worried about is the truck is probably 75% pavement pounder and will be 25% "offroad" (fire roads, mild trails, etc) and with the stiff spring rate of the stock torsion bars and the 2.0's being reviewed as stiff on road - is it money well spent on bumping up to the 2.0 LSC right off the bat? What if I only did LSC in the front and 2.0's out back with a mini pack?

It looks like there were several different torsion bar spring rates offered in 01-07 2500/3500 trucks, have you seen or heard of anyone playing with different bars to tweak performance? If my leafs are sagged out in back, I'm willing to bet my torsion bars have lost some spring in their step too... so I might look at replacing them eventually

 

[Chevy1925]

its kind of up to you. the LSC will make a difference you can tune in but a 2.0 shock can only take so much for high speed and low speed on that heavy front end before you are just well past its capabilities. the really stiff stock torsions actually kinda help make up for its lack of control under heavy use, its just a matter of getting the shock rebound under control, if it can control it. you could always put a small flutter in the compression stack if it just doesnt smooth out but i would be curious what they even send you for internal valving like: how many bleed holes are open, what the stack height is, and what shim thickness used. the LSC is a great way to slow/stop cavitation behind the piston head from the IFP moving when it shouldnt be. In other words, you plug all the piston bleed holes, put a .020 shim stack on compression, go out and hit some hard hits off road. What happens is the 200psi of nitrogen pressure isnt enough to force the oil through the valving stack and make it work correctly, instead, the IFP compresses the nitrogen and no valving action happens (this can make you chase your tail when valving). it also creates cavitation behind the piston and it eats up the piston and shims over time. So the LSC is another shim stack in the resi (older style lsc are just bleed holes) and an orifice you are now adjusting to allow a certain amount of fluid to enter the resi at a specific rate. this combats the IFP plunge and makes the shock valving work better. another bandaid is more nitrogen pressure in the resi up to about 320psi, beyond that you run the risk of blowing the canister off the caps under full shock compression.

so its really dependent on your driving style. its very hard to make a 2.0 shock, torsions, and 4k unsprung front end with 8-10" of wheel travel be smooth on and off road while driving semi aggressive.

if it were me, i would save for a set of external bypass shocks in the 2.5 or larger area. thats going to get you the closest to having your cake and eating it too. thats a "best case". if i was to be more budget minded, id take a set of the LSC shocks and put them on the front but i would also be very much willing to valve them my self. you first need to know what shim stack is in there and how many bleed holes are open (generally they come with 2 bleeds open), put it on the truck and drive it. see how it feels on wash boards or on rough road. then take some bigger hits with speed like ruts or areas where the front end is using alot suspension movement. note how it feels and you can always post here. i can help you through tuning them. lots of ways to skin a cat in there and you really cant be "wrong" if it rides how you like it. its opinion based. id have no issue putting 2.0's on my truck and have contemplated doing that sooner than later. the stock ranchos dont have enough rebound for my liking though they are miles ahead of the older gen stock shocks.

rear is difficult to be smooth all the time, extremely light compared to the spring rate used = difficult shock tuning. cant work miracles

 

[fl0w3n]

its kind of up to you. the LSC will make a difference you can tune in but a 2.0 shock can only take so much for high speed and low speed on that heavy front end before you are just well past its capabilities. the really stiff stock torsions actually kinda help make up for its lack of control under heavy use, its just a matter of getting the shock rebound under control, if it can control it. you could always put a small flutter in the compression stack if it just doesnt smooth out but i would be curious what they even send you for internal valving like: how many bleed holes are open, what the stack height is, and what shim thickness used. the LSC is a great way to slow/stop cavitation behind the piston head from the IFP moving when it shouldnt be. In other words, you plug all the piston bleed holes, put a .020 shim stack on compression, go out and hit some hard hits off road. What happens is the 200psi of nitrogen pressure isnt enough to force the oil through the valving stack and make it work correctly, instead, the IFP compresses the nitrogen and no valving action happens (this can make you chase your tail when valving). it also creates cavitation behind the piston and it eats up the piston and shims over time. So the LSC is another shim stack in the resi (older style lsc are just bleed holes) and an orifice you are now adjusting to allow a certain amount of fluid to enter the resi at a specific rate. this combats the IFP plunge and makes the shock valving work better. another bandaid is more nitrogen pressure in the resi up to about 320psi, beyond that you run the risk of blowing the canister off the caps under full shock compression.

so its really dependent on your driving style. its very hard to make a 2.0 shock, torsions, and 4k unsprung front end with 8-10" of wheel travel be smooth on and off road while driving semi aggressive.

if it were me, i would save for a set of external bypass shocks in the 2.5 or larger area. thats going to get you the closest to having your cake and eating it too. thats a "best case". if i was to be more budget minded, id take a set of the LSC shocks and put them on the front but i would also be very much willing to valve them my self. you first need to know what shim stack is in there and how many bleed holes are open (generally they come with 2 bleeds open), put it on the truck and drive it. see how it feels on wash boards or on rough road. then take some bigger hits with speed like ruts or areas where the front end is using alot suspension movement. note how it feels and you can always post here. i can help you through tuning them. lots of ways to skin a cat in there and you really cant be "wrong" if it rides how you like it. its opinion based. id have no issue putting 2.0's on my truck and have contemplated doing that sooner than later. the stock ranchos dont have enough rebound for my liking though they are miles ahead of the older gen stock shocks.

rear is difficult to be smooth all the time, extremely light compared to the spring rate used = difficult shock tuning. cant work miracles

Bold pretty much confirms what I was thinking, for about double $$ the basic 2.0 smooth bodies I get the LSC 2.0's, but if they're only "good" for a few minutes in the rough stuff it doesn't really seem worth it over the 2.0 smooth bodies right now. Sure I could probably tune them for smoother on-road ride and not out-pace them, but in that case I'd just go Bilstein 5100's for even cheaper.

The LSC's are a decent jump over the smooth body 2.0's, but it seems like it would be better money spent towards the 2.5 DSC or even the King 2.5's which are a tiny bit less but they don't have dual speed compression easily adjustable from the outside.

I've never revalved a shock, but I'm always willing to learn. The thing I liked about the DSC or LSC was being able to just turn a knob and test the results, and like you said, it's pretty subjective so I could just keep turning until I find what I like.

The 2.0 smooth bodies can be revalved if I wanted to really get after it, right? If so, that might be fine for me while I "grow" into the truck and my adventures/skills.

If I do wind up going 2.5s and spending that type of money, I feel like it only makes sense to do spring under deavers in the rear with DSC's to adjust for towing and empty loads

Thanks for all the info on shocks, I gotta read up about IFP's now

 

[fl0w3n]

So... just ran out of fuel for the first time. I forgot the previous owner told me the sending unit is wrong and he’s run out around 1/4 tank twice.

is the sending unit physically bad and need to be replaced or is it a software thing?

 

[2004LB7]

Typically if the sending unit is wrong but not bad, the gauge will read backwards, this can fixed with tuning. When you run out at a quarter tank, it is normally either a crack in the pickup tubing on the sender or the venturi device fell out the bottom of the pickup bowl. It is possible to have jacked up tuning too cause it too.

 

[fl0w3n]

Typically if the sending unit is wrong but not bad, the gauge will read backwards, this can fixed with tuning. When you run out at a quarter tank, it is normally either a crack in the pickup tubing on the sender or the venturi device fell out the bottom of the pickup bowl. It is possible to have jacked up tuning too cause it too.

Thanks, although I should clarify the scale is off and it’s actually an empty tank at around 1/4 left

pushed it one day and dash said 40 miles left and about 1/8 tank, light wasn’t on yet. Decided to fill up and got 25.75 gallons into it. I’m pretty sure CCSB still has a 26 gallon tank. I know my LBZ with 26 gallon tank had the light come on around 6 gallons left.
Oh and just now after dumping a nearly full 5 gal jerry can, I went and filled up with 21 gallons at the station.

so I’m not sure it’s cracked since it uses 26 all gallons. Stock tuning truck as well.

I don’t mind replacing it for peace of mind... just curious what is actually wrong.

should I go AC Delco or Delphi on the replacement?

 

[Chevy1925]

if someone put a long bed tune in it, it will read off like you are stating. light comes on, on a long bed at 29-30 gal. someone may have "flashed it back to stock" and used the wrong OS for it.

 

[fl0w3n]

if someone put a long bed tune in it, it will read off like you are stating. light comes on, on a long bed at 29-30 gal. someone may have "flashed it back to stock" and used the wrong OS for it.

Interesting, any way to check what OS is on it with a Tech 2?

 

[Chevy1925]

i think a tech2 will show the OS. i know an MDI2 will.

 

[DAVe3283]

The Tech2 will show the OS and segment IDs. You can enter your VIN on http://calid.gm.com/ and see what OS it is supposed to have, to see if someone loaded the wrong one.

 

[fl0w3n]

I got this off the site you linked @DAVe3283 and I found a list of ECM info that matched the Part Number part of the list but couldn’t find the CVN info which I assume is the OS calibration?

 

[fl0w3n]

Also, I think I know at least part of the reason my injectors haven’t lived a happy life...

Also found a piece had fallen out of the bottom of the old sending unit and was laying on the bottom of the tank.

 

[DAVe3283]

If the "part number" matches, it is the right base tune file. The CVN is a checksum and would tell you if the tune was modified or not, but you know it is based on the correct OS at least. I don't remember how to check CVN with the Tech2.

 

[fl0w3n]

Okay that makes sense.

the weird thing is when I took the sending unit out I plugged it back in out of the tank and had a buddy play around with the arm while I looked at Measured/Reported Fuel Levels on the Tech 2

it seemed inconsistent on the low end, but I was able to get the dash light to come on even with the old sending unit.

holding both sending units at the same location and comparing, the arbitrary location we picked showed 31% on the old unit and 28% on the new.

couldn’t really make sense of the whole situation, but figured I now have a brand new AC Delco unit in there and that’s leaves the only other potential problem is with software

I guess I’ll have to fill up and then make sure I pay close attention to the miles to see if it’s making sense towards empty... I don’t want to run out again testing the new sending unit haha