This has probably already been discussed, but I just noticed yesterday on the drive to work, RPMs dropped to 1500-1600 around 55-65 MPH. Anyone experience this issue? My apologies if this has been discussed already.

 

v

Yes, its a rare condition called "4th gear". I have the same problem. Only solution is to turn OD off.

Just kidding. That's perfectly normal rpm for that speed when just cruising along.

 

1,500 is what mine runs at 55 and I have 3:73's. At 65 is around 1,900

 

Maybe I've just never noticed. By normally my truck stays around 21-2300. Just didn't seem right to me.

 

uhh... your transmission has these cool things called gears, and they spin and make your truck move. yeah there's 4 of them in there.

that there "problem" you're having is what us edjamacated people's like to call "shifting to 4th gear" otherwise known as "overdrive"

 

.... You don't have to be a dick. Allow me to elaborate a bit more since looking back at my original post I see o didn't mention everything.

It shifts first to second.. Staying above 2k.
It shifts 2nd to 3rd.. Staying above 2.1k..
It shifts 3rd to 4th staying above 2.1k.
Shifts JUST fine from 3rd to 4th.. Staying at or around 2.3k. Then drops drastically and shoots back up as soon as I hit above 65.. It's NEVER been that low on the RPM.

 

You should never be at 2300 rpm in 4th gear at 60 mph. Unless you have 4.88s in the axles & 32" tires. Sounds like it's not actually shifting into 4th or the torque converter is slipping. Usually, under normal acceleration, it will shift into 4th at about 45-50 mph.

 

Charlie it's always been high like that which is why I thought this was way outta the ordinary.

Bought it last April when I started a new job. Haven't had any major issues other than a misfire forever ago.

Ah well. I guess I'll see what happens today on the road.

 

Count the shifts & record the rpms under normal acceleration. This will give you an idea of what is happening. If you can find a shop that has diagnostics with live data they can tell you if in fact the torque converter is locking properly. Have you changed the fluid & filter in the transmission? If not, wouldn't hurt to try it.

 

Trans fluid exchange is on the table. Someone told me it isn't worth it. Truck has 164k on it.

But I'll check RPM level when I head to work tonight.

Didn't think about the shop thing.

Should just grab a new 250.. I build the damn things.