Okay this is probably going to sound stupid, and I didn't know how to phrase it. This is my first vehicle, my 2000 Dodge RAM, and I have kind of a dumb question about it and RPMs in general.

Okay my engine seems to knock under load at about 2500 rpm, but I only notice it if I'm trying to gain substantial speed from a low speed, like flooring it at 20 mph to get to like 60+, it doesn't seem to do it if I slowly gain the speed and break 2500 rpm.

But this is where I'm confused if vehicles are designed to do what I'm about to ask, or if I have a problem. When and if I floor it, my rpm climb to around 2500~ but as soon as the vehicle reaches about 60 mph, the rpms drop to a steady 1500~ and keep the 60 mph and continues to gain speed while the rpms climb slowly, pushing 70 it's never gone over 2000 rpm, but if I push it and floor it it'll rattle.

Dumb question I know lol, but are they designed to do so lol?

 

Auto or manual. Hows the steering any shaking? Vibrating? Also would u say the pedal responds quickly or feels sluggish? I had a similar problem with getting to higher speeds.

 

weird kinda sounds like the trans is going limp mode on you but im not sure. someone else will chime in

 

Automatic, no vibrating or anything and no loss of power it seems, it just usually happens at about 60 mph, when I hit 60 the rpms go down to about 1500 but it doesn't seem to lose power or speed and starts building up rpms again when sitting at 60 if I give the pedal more gas, I read somewhere that it was the torque converting doing it's job?

It kinda seems like it is similar to when it's a manual and you shift gears, it just drops about 400/500 rpm and the engine settles down because of less rooms, but as far as I can tell it loses no power.

Forgot to add, this only seems to happen times when I quickly attempt to gain speed from like 15mph to 60mph, like entering the freeway, or just flooring it on a straight empty road, it's mainly when I attempt to get the rpms past 2000 to try and hear if the ticking sound from the engine at high rpms is engine knock, but once it gets to about 2200/2300 it'll drop to like 1700, and as long as my foot is still on the pedal will climb, I've never taken it past 70mph, and have never seen rpms go above 3000 lol.

 

I had a sluggish problem with pedal not responding due to a blown plenum gasket. My truck doesn't like above 70mph.

 

Probably more than one problem. Just to hazard a guess, I would say blown plenum, and TV cable out of adjustment. At WOT, you should be almost bouncing off the rev limiter before it shifts. (around 5200 RPM)

 

Ugh lol screw this damn truck I sink $ in to only find a possible new problem, ugh! I never take it above 70 and even tho the rpms drop at wot, but it doesn't seem I lose power, I'm just gonna drive the dang thing and let it rot lol, plenum blown or not, it still runs at 231k miles good, and so far I haven't notice oil loss or MPG drops. I'm done ocding over all the problems I've already tried fixing lol, I should of expected issues galore with this many miles, thanks for the help guys.

 

It's really not that big of deal to adjust the throttle valve cable, you can do it yourself. There's a thread on here somewhere that explains how to do it. And if you have about $200 or a little more you could fix the plenum yourself and a few other things and have yourself a nice running truck....granted the rest of the engine is in decent shape (compression etc). that many miles on it, you're gonna have to start putting money into for little things. Don't give up on it or it'll give up on you!!

 

I just fail to understand why if I have a blown plenum why I have yet to see any significant signs of it in the 9 months I've owned it, the truck seems to run great, and I get about 11mpg in town driving as that's whati mainly do, and ever since the oil change about 700 miles ago I haven't lost any oil yet. I do get pinging at around 2200+ rpms but I rarely ever take the truck up past those rpms, even on the highway/freeway, as I never drive above 70. I am strapped for cash, and have already sank so much into it lol.

 

At that mileage, it IS going to be a rolling repair bill...... Things wear out. If the plenum hasn't been fixed..... it can cause an assortment of issues, but, not necessarily all of them at the same time. Best bet: Check it. See what it looks like. You may have gotten lucky, and a previous owner may have already fixed it.