First impression towing with 6.9 NA

Cubey

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I wanted to post this while it’s fresh on my mind. I just towed my travel trailer for the real first time on the highway. Only about 20 miles but it’s enough to give me an expectation. It’s a stretch of highway with a few rolling hills.

I can see why a lot of people are down on NA IDIs. It really is a “slug”, a word I often see described. Getting it up to 50-55 takes a while (like an 18 wheeler with a load of logs) and maybe it’s an issue with my throttle cable, or something else, but I have to really mash it hard to keep it at 55. (Assuming my speedo is still showing 5mph faster than I’m going). The speedo sat mostly at 55 (so really 50) unless I have it an extra hard press. You need a muscular right leg to stay at 55mph. That would get tiring even so. Basically you have to nearly floor it keep it at 55? Might need timing?

Temperature was around 190-195, never reached 200. No really big hills though.

My tach reading is questionable at times but it stayed around 2000rpm at the 55 (50 actual) speedo reading. It wasn’t screaming so I suspect it was at least close to accurate.

If I had it to do over again? I’d have gotten a turbo IDI or PSD if I could have afforded it at the time. Yes, turbo is an option on this truck, but it means half an engine rebuild so it’s not really viable, at least right now.

At least I have a good excuse for staying well below the speed limits, it’s all my truck can do!
 
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chillman88

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Yeah mine is similar but mine might be a little stronger, not sure. Apples to oranges since you have no overdrive and 3.55 gears vs my truck having overdrive and 4.10 gears.

I will tell you that it made quite a difference changing an old fuel filter, and running a few tanks of MMO through. Timing can make a big difference too.

Mine is still a slug, but driving home from Texas I don't think it would have pulled a motorcycle trailer and I've since hauled a pretty decent sized trailer when we were moving. I find myself downshifting a lot when towing though. 4th gear is needed to hold 55 with mine most of the time (5 speed manual).
 

Cubey

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It got a new fuel filter about 10 months ago. Same with air filter. I sometimes run diesel kleen. I guess I need to always. I ran the winter version during below freezing temps.
 

Cubey

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You know I just realized something, I actually towed before at highway speeds with this truck. I forgot all about it until just now!!

It was with a uhaul car dolly and a 2003 Pontiac Vibe. It was right after I bought it, that’s how I got two vehicles back home.

It didn’t seem like such a slug then but it was less of a wind break too. Hmmm.... it could very well be timing or something else going on.
 

chillman88

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Mom had one of those before my brother totalled it. Peppy little ****** for having a tiny little... 1.8L?

Yeah not only far more aerodynamic but probably a bit less weight too.

Anyone near you in the "Timing Registry"?

Wouldn't hurt to get a few more runs in too. I've had fuel that was less than stellar impair performance. I only know because I noticed a decent change when I filled up at a different station. They might still be using winter fuel where you are? That could make a difference too. Just a thought.
 

Cubey

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Might be 1.8, it’s the Corolla engine of the day.

I didn’t have the camper shell on the truck then either.

I messaged somebody yesterday in Arkansas on the registry and supplied my cell # but no reply. They haven’t been on the forum for over a month I think I saw. Somebody is in central Missouri, which is kind of along my way so I may message then also in a day or two.

I doubt it’s winter fuel. My mpg recently went up from 10.5 to 11.5 city (not towing) so I bet that was the change over. I think I’m getting 8 city when towing. Too soon to tell.
 

Ethan Smith

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If your getting 11 or so mpg and 8 city towing you could be having some blockage issues. My 85 gets 16 in the city, c6 auto 3.55 rear, and its no spring chicken let me tell you. Is your smoking at all? How much oil it burn?
 

Cubey

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It’s 55 most places with trailers. I did 55-60 with the car dolly in as much as a 75 zone. (Texas). I don’t mind staying at 55 but it seems to want to stay at 50 unless I really put my foot down hard and leave it there. Maybe I had a head wind.
 

Cubey

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If your getting 11 or so mpg and 8 city towing you could be having some blockage issues. My 85 gets 16 in the city, c6 auto 3.55 rear, and its no spring chicken let me tell you. Is your smoking at all? How much oil it burn?

It burns oil but none comes out of the oil filler. It got a new CDR about 7-8 months ago. Really bad valve seals? Oil consumption varies but for a time I wasn’t sticking with one oil, I kept topping off different brands. I’ve stopped that now. I put 1qt of Lucas HD Oil stabilizer with fresh oil last week. They say you can put up to 20% capacity (so 2 qts). Might just have to try that. Although if it’s the valve desks, not blow by, that probably won’t help much.

It leaves a grey (blue?) cloud taking off with the trailer. Even without the trailer, the right rear wheel is coated in soot. You can see it in my picture. It has a hubcap on it that’s spot black.
 

Cubey

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Oh forgot to answer the question, probably no more than 1qt every few hundred miles. I don’t have an exact figure, sorry.
 

franklin2

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I was going to chime in and say your experience was normal. But the fuel mileage is way down, I am suspicious of that. I have 4.10's, 35 inch tires with a 4 inch lift. N/A and with the zf 5 speed I get 15mpg on the highway all day long. That is empty. I have never checked it loaded though except when I had the c6 in it. At that time everything was the same except the trans, and I was getting 12mpg empty, 10 mpg loaded.
 
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Sidewinded_idi

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Sounds like a worm ip, that blue smoke is I burnt fuel. You need to time your truck. My 7.3 would get 22mpg highway if I stuck to 60. Time your truck and it’ll be a lot better
 
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