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Discussion Starter · #1 ·
Whenever I get on the highway I have problems maintaining speed. On flat ground the thing does alright, but on a hill the only way to keep my speed is to turn the O/D off and run at 3500rpms up the hill. I usually have the thing floored on flat ground too.

The truck's on 35's and has 4:56 gears so I'd imagine it wouldn't be that bad on the highway. Normallly I'm running about 1900rpm at 70-75mph. I can feel the truck shifting twice when you turn O/D on/off, is the trans skipping a gear or something? It really kills my gas mileage running like I do now.
 

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I can feel the truck shifting twice when you turn O/D on/off, is the trans skipping a gear or something?

It's not skipping a gear, what you are feeling is the torque converter unlock prior to shifting. This is normal.

As for the lack of balls, i dunno. With 4.56s you should have sufficient leverage.

How many miles you got on the motor?
Any fluid consumption? (other than gas)

When you say it's killing your gas mileage, what are you getting? Around 10-12 is about normal for a gasser with lift and tires.
 

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ya that doesn't seem right. i've got 35's and 4:56 and i can maintain speed up decent size hills in o/d. in fact my o/d button doesn't even work, so i can't shut it off. i'm turning about 2000 rpm at 60mph with the tc locked in o/d. what you are feeling is the converter unlocking, which probably jumps you about 300 rpm or so, then kicking down to 3rd gear. next time you're on flat ground at a steady speed, hit the brake very lightly, you'll see the rpm's jump for a second, then go back down. that is the boo switch unlocking the t/c. is the tranny slipping, does it sound like its slipping? does it surge, make any noise. you will hear it slipping, it doesn't put the load on the engine when the tranny is slipping, so you will hear the engine revving higher, but it will be like revving it in park or neutral, like no load on it.
 

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:withstupid: Had the same issue till I got 4.11s, if you have 4.56s you should be good.

How many miles & what engine?
 

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I ran 40's with 3.55's in my red truck for a while and it would hold OD just fine on flat ground....with 4.56's and 35's you should have gobs of power.... Have you adjusted the transmission bands and changed the fluid and filter lately? ALso...as stated, could be in the converter. You have a 318, mine had a 360, but the 15HP difference is unoticeable for this purpose...
 

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You have a 318, mine had a 360, but the 15HP difference is unoticeable for this purpose...

I agree that the horsepower difference is negligible, but the torque difference is pretty substantial.
 

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Sounds to me you are just lossing power, check the cat, it could be plugged up.
 

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Discussion Starter · #10 ·
Yea it seems like I have no top end power at all. The trans only has 6k miles on it so I suppose I could rule that out. Haha I poseted this topic during class at 8AM so I wasn't quite thinking clearly.

The essentials: 5.2L engine with about 110k on it. Like I said, it got a new trans over the summer, and it consumes no oil. The truck has tons of power when flyin through mudholes and it's got plenty of grunt for climbing hills and does burnouts with ease. I can break the rear end out at some scary high speeds, the truck acts like it has 35's and 4:56's.

When I get on the highway it has no problem getting up to speed. Once I let off the gas a bit it shifts into overdrive and that's where I seem to have problems. It almost sounds like it's boggin out when you try to accerate and the thing wont downshift unless you let off the gas completley and then mash it to the floor (which is easy cause it's so annoying). I'm thinking something may be out of adjustment? My speedo is off, but with some simple math I've concluded that I'm running roughly 2000rpms at about 63-65mph, which is close to what BR said his does. I've also noticed that the truck seems to shift very quickly sometimes when I'm dragging down the road. Whew, long post! :sorry:
 

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Honestly...I think it is just the 318 engine. Even with 4.56 gears the weight of the larger tires/diameter, poor aerodynamics and the low 5.2 HP, I would a$$ume it's normal???

I have 33's/3.55's and the 5.2 and it is fine on flats but won't hold an incline for Sh!t! UNless I'm going 80. But it pulls the hills pretty good when it does shift down.

You said it gets up to speed fine, just won't hold it on the hills in O/D? Again in my opinion, sounds pretty normal for your set-up.

You said it plows through mud and hills strong, but is that in 4Lo?

If it is something, then I need to know too...Good luck!
 

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I have the 360 with 33"s and 4.10 gears and experience a similar problem. I have 66k miles on the truck. Going up a hill doing 60 or 65 or so in OD you can get it to maintain the speed but not really accelerate much if you turn O/D off or floor it so it downshifts it accelerates like I Want but wont in O/D. My Honda Accord is the same way it just downshifts so I think it's something normal for automatics. Maybe not though.
 

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I'm having a bit of the same issue as most of you are. But I have also noticed my MPG is going downhill quick. The exhaust tips are pretty sutty for what seems like its running rich. At idle, I hear a slight pop every couple seconds thru the exhaust...

Not sure what it is, and havent had time to check it out...

Rick
 

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I've got the 360, 33s and 4.10s and if its much of a hill at all I will loose speed until I made it downshift OR I turn OD off...I usually just turn OD off because if not it will just shift back and forth going up the hill. I hate dodge transmissions :wall:
 

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Its just the 318 has no balls down low in the rpms. I have 39.5 boggers and 3.55 gears. When it was stock, It would do the same thing yours is doing around 75 mph or so in overdrive. I just think the 318 doesn't have enough rotational mass to keep the speed up. :bigthumb:
 

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Discussion Starter · #17 ·
Haha I guess it's normal then. Also, I rarley have the need for 4low, so 90% of my offroad time is spent in 4hi. Even when I pull someone out, 4hi has enough torque to break the tires free.

Would a Hypertech or similar programmer help out the low end at all? I need to figure this out because there's no flat highways around here and I don't like to have my truck screaming up hills near 4k rpm (although the people behind me get a kick out of it).
 

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NJ Ram: If you have to let all the way off and then slam it to the floor to make it downshift, something is not working correctly. Check you TPS or the kickdown/TV (don't know the exact nomenclature) cable.
If you have to the floor, are traveling less than 90 mph, and it's not downshifting into drive - something is wrong.

granted, i weight a little less cause I'm caseless, but my 318 holds speed good in O.D. And it has low end grunt, not as much as a 360. but hey, it's not stock either. To give you an idea, it would eat my co-workers 5.7L Z-71 (which is mostly stock except for exhaust + K&N) 0-60.
 

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Could be a blown plenum gasket, loosing vacuum, which on most occasions wouldnt be noticeable when the engine is rapped up. I bet thats part of your trouble. I've fixed my share of them and it usually feels like somebody kicked the truck in the a$$ after you replace a blown one....... could be your problem.
 

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but if it's not shifting properly would that still point to a plenum gasket?
the shifting is controled by the TPS and TV cable right?

edit: and he says he has plenty of lower speed power, if he can lite the tires off and accelerate fine it doesn't seem like he has a loss of acceleration power typically a$$ociated with blown plenum gasket syndrome.

MIL light on? any stored codes?
 
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