(my apologizes for a duplicate post....original post got messed up by my own reply)

Ok...fairly new diesel owner and new (to me) truck. Have a question. I have 200k miles and the only mod is the 6637 intake.

I am happy with the power, can really feel the boost kick in when it hits 15-18 psi. So...this weekend I put a trailer behind it. Just a simple trailer with 2 ATVs (maybe 3,000 total...probably more like 2,000) Anyway, when going downhill or on a flat grade I could keep 70 mph with no problem. However, when going up any grade (I live in a flat area...not in the mountains) it has trouble keeping up. Let me explain more.

The engine sounds reasonably quiet most of the time...have a intermitten rattle (louder than normal rattle) under load when in the 1500-2000 RPM range. Doesn't do it at full throttle, doesn't do it at idle...but does it everywhere in between. When towing and hit a grade...truck stays in over drive, sounds like my old gasser with very bad gas (the intermittent rattle comes back) and just feel sluggish. Almost like an engine miss....not hardly bad enough to make me think tranny slippage. If I give it more and more juice (to hit 8-10 psi boost) it (barely) keeps the speed and does not downshift....but I thought it shouldn't be so hard to do so.

Do I have a problem with my fuel pump or fuel system in general? Is type of engine/truck slowdown on grades normal? I have a feeling that with any sort of 'real' towing load I would have real issues getting up a simple grade at 60-70 mph.

 

Bump....thoughts?

 

When was your fuel filter last changed?


Smokie

 

check all 4 boots on IC pipes and the 2 under the spider pipe going into the valley for leaks,crack,splits and loose clamps..then check the up pipes on manifolds under the truck going up to the back side of the turbo for black soot build up...where is your boost gauge hooked up to??do you have EGT gauges? what are the temps??does it smoke at all??what color?? has the SES light ever come on?? we can not see what the truck is doing so we need every detail you give us...

 

For what it's worth, I can't believe the boost I can build since I installed Bob's (DieselSite.com) boot kit. And I just put on the upper boots on the IC pipes. Waiting to pull my turbo for rebuild and other stuff then will add the lower boots on the Spider.

NOT hijacking just reinforcing the importance of a good seal. I can't wait to tow next Sring to NM.

*I could see little leak marks in the oil residue where the boot connects to the Spider. Those thin cheesy silicone boots didn't work well for me. And the blue one was not original (it split).

Hope this helps

 

i have his boots as well..its hard to pull them off of the pipes with out clamping them..they do grag the pipes well..and they dont swell as much as stock boots...

i luv that sig

 

His boots are top notch quality. If aocabrown is having a hard time making 8-10 lbs boost pulling 3k then I think you're very much on the right track with boost leak.

Side note, a friend of mine stopped by with his "Superior" (as he describes it) 6.0 and I showed him his boost leaks then showed him my lower boots (still in box). He'll probably be ordering them soon. Heck, even if you don't have little air-spray marks in the residue, just the residue alone is evidence of leak (IMHO).

Glad you like my Sig. Between my brakes yesterday and the furnace dying last night at 2200, it's hard to save up on the side (ie unnoticed) for that stuff.

 

Ok..more info. Yes...first thing I did was change the fuel filter (2 weeks ago). Also running Diesel Kleen with each tank of fuel.

I'm not having trouble hitting 18-20 PSI boost. What I was saying is that I'm cruising along at 2,200 RPM...70 MPH and about 4 lbs of boost. When I hit a grade the engine starts to sound like a gasser with water in the fuel (extra loud pinging) and the only way to make it keep speed is to keep pushing on the throttle until I'm doing 8-10 lbs of boost (not enough pedal to force downshift).

My previous gasser would have just downshifted often (which I hated). This 7.3 doesn't do that but what I'm trying to determine is if this level of struggle under relatively light load is normal. I believe if I had more lbs behind me I would either have to give MUCH more pedal or do downshift and do 40 MPH up these small hills.

 

EGTs at about 500-600, and boost guage connected as a T-connector in MAP line area. I have checked for boost leaks (soot) on up-pipes and can't find anything wrong. Will be replacing all boots soon just for the heck of it but all are clean around them.

 

Ok, give us a Sig, if you don't have enough post to do it then just post it. This will help us help you.

 

SIG added. I feel 'priviledged' to finally be able to do that. This place is great.

 

are you under 1/4 tank of fuel when this happend??? if so..this may be cured when you get the ITP intank kit put in

 

Both...was under half tank. Decided that might be the problem so I filled up. I tried to think it was a 'little' quieter but still seemed to have the same issue under load.

What I'm really wondering is if the ITP tank will be the "cure" or just a nice enhancement....or if I hvae a larger issue like a bad injector that rattles like heck at 1,400 RPM and though I can't hear it as much at 2,200...could still be causing power loss.

 

does it smoke any?? if it was air in the line from sucking air..it will take 50 miles or so to clear it up..when i did my ITP intake it made my truck alot quiter but took about 100 miles driving to do so..do you have or a friend have AE( AutoEnginuity )??? have you ever got the SES light??

 

if you have cruise set at 70 it should downshift by about 65