my 97 2500 12v 4x2 only tops out at 95 close to 100 but I'm redlining it. I was trying to find out what gears I have?? and what gears are good for toping out a little bit higher so I can keep up with smaller cars on the highway and also to save gas cuz on the high way I run about 80 mph all the time and I just suck down the gas there. so anybody know?? thanks guys


AP

 

just guessing i would say you have 3.73s. If you want better speed try 3.54 ratio I think thats the next size down. You'll loose some on bottom end but gain alot on top end.

 

I though that the 2nd gen trucks came with 3.55's or 4.10's?

By redline do you mean 3,000 rpm? Sounds like 3.55's with stock tires.

http://dodgeram.org/tech/specs/axle/5sp_tires.htm

 

a 3k gsk or a 4k gsk will solve this problem without changing your gears. The 3k gsk will run you about $125 bucks.

 

I doubt you would get anywhere close to 100 mph without some form of GSK. Stock tires and 3.55 you will hit the governer around 75 to 80 mph.

Cruzing at 80 is going to hurt your milage. Best milage for a 12 valve seems to be around 1900 to 2200 rpm.

 

That's were mine tops out as well 160kph(100mph), i'm not at red line though i am at 2500rpm where it defuels with 3:55's. I i will be adding a 3k kit in the future.

 

When I went looking for a truck , one of the things that I thought that I had to have was the 3:55s , the way I had it figuered was that the Cummins can have a lot more HPs added to make the 3:55s tow and the only thing [ excepting tires & wheels ] you can do with 4:10s for MPGs & lower RPMs is change the ratio , so now you have to decide if you want to spend about $1,000 for tires & wheels or up to double that [ if you pay to have them changed] gears .
Just went back to check your info , I was assuming that you had 4x4 , so cut the gear $$$ in half , now its a tougher choise being about the same $$$.
When running on flat ground I've seen the tach just on the top side of the 1,250 mark at 50mph with 265-r73-16s.

 

My 93 with stock gov spring would do over 100, 3.55 with 235-85-16's and the 47RH helped abit. Mind you at that point I was almost completely defueled around 2700-2800 rpms. Mine does 82 at 2200

 

i have owned trucks with 4.10s and 3.55s. i would never go to the trouble of switching the gears. a rpm kit fixes any runing out of mph problems.

 

There is no question you have 373's. I have 410's and i can only hit 82 at about 3050 rpm's. And my buddy who also has a 97 and a 5spd can hit 113 at 3050 rpms. And your right in the middle so it cant really be anything else IMO.

 

Well before my GSK, i used to hit 85 mph at about 2600-2800 RPMS or so, and would top out at so to say about 100 or so with the banks plate and the 285s, now i can go up to 120 easy and still be fuelin, but with lack of headwork, i dont dare..I have 3.55's by the way....

Rick

 

woops Sorry i ment 355's. I forgot that that my buddies has 285's or somethin real high.

Rick

 

You have 3:54. My '99 is the same. I have 245/75R16 and it defuels about 89 mph and creeps up a little from there. I have seen 93 before but not at readline. I changed from 4:10 to 3:54. And I would have wen 3:31 if they were not almost $700 for the gear set. They are a dana only part. When I do tires I will probably go with a 235/85R16. I think that will give me the rpm/speed I want. 75 mph at 2150 or so. Right now I'm at 65MPH at 2000. With 4:10s I was 60 at 2150.

Randy