Hello every body,sorry for my bad english,i'm Italian boy... but I try to explain my questions:i wuold buy a new Ram 2500 with cummins but i would also "build" with some special parts....I ask directly on this forum because you know better then me the truck...

So,with 6'lift kit is possible to fit 37 tyres without body lift?or is better 36(12.50/13.50 or....)always w/out body lift?

in the stock model  there is 3.73:1 or 4.10axle ratios...i can use this ratios or i must change for use this tyres?

for a light use in off road the post/ant axle (AAM perhaps)is good for this tyres?

what the different between Dana(60 or 70 for example) axle and AAM axle?what's the strongest?

sorry for the number of the questions but in Italy about this truck don't say a lot...!

Nico

If you plan to run oversized tires you really need to change geerin because you are effectively cahnging your overall gear ratio to a taller gear. With 36 or 37's you 3.73 is like a 3.07 with stock tires. Some will boost engine in a effort to overcome this but it also adds a lot of strain to driveline too. A 4.10 ratio would still be too tall with 36's but better than a 3.73. A 4.56 would give you about the same overall gear ratio with 37's as 3.73 would with stock tires so overall performance would be near stock minus the extra drag of tires and lifted truck and have minimal impact on drive train too.  

thanks...for the axle ratios...!

for tyres?is possible to fit 36 (or 37)with only 6' lift kit?i always see the 6 lift kit with 35...?there's a motivation? or this is the best combinations for improve the capability of the truck?

i would like to fit the 36 or 37 because i see fit on  35, but there's a lot of space between the border line of tyres and the mud flares on the body...so you see  "little tyres"  and a tall body with a lot of space empty...and is not so good for aestetic result...perhaps with a "big" rig (18x10 for example)the optic illusion will be reduce??? 

at usually sorry for my bad explain

Nico

I would limit it to maybe 35's if it is a 1500 because of axle strenght and brake size. You will be able to play a bit harder with 35's than with 37's without breaking anything and have a bit less front end trouble generally too with the smaller tires for what it is worth.  

6" lift on a 2500 will be more than enough for 37's and definately regear to 4.56 or 4.88  

with 37's I would say 4.88 minimum with 5.13 worth consideration if you play hard.  

thanks everybody!

Other question:there are other parts that i must change?

for example what about the fenders?  (with 36 or 37 12.50)

Nico, what exactly do you have for a truck,3/4 or 1/2 ton or are you looking to buy a ram  

yes i'm looking to buy a Ram 2500 cummins(or power wagon when will be avaible with cummins) and i wuold like to learn by us some trick to build my favorite truck when this will be at home...

so in short:

36 or 37/12.50

4.88 for gears

6 inch lift kit

fenders?width?

other advice?

thanks for reply

If you are serious about the off road rig, forget the Cummins and stick with a gas motor as the front end will weight about 800lbs less with a gas motor and it will handle better jacked up and not sink as quick in mud too and frontend will also hold up better if you play hard. Cummins is a good engine but really to heavy for chassis plus a wide RPM range of a gas motor is a asset too if you play hard vs the diesel very limited RPM range. Driving thru deep mud with a cummins up front is like doing it in s gas engine truck with a snowplow hangin on the front because the ground weight on front axle will be about the same and carring a plow through the mud is not a good combo.  

yes this problem could be true.....i understand...but i also use the Ram for daily use,for go to school,for carry my ktm on the race track and so on....

perhaps the fuel economy is better(with these price....)

so if i want play very hard i don't use this truck but, sometimes for mud trips with friends, nothing of extreme....in fact i will buy one set of A/T tyres for highway use and, for the future, another set of tyres that change when the play become hard..!

Nico

Unless you put 200k to 300k on the diesel without a break down you will never break even on the extra cost of the engine and the extra maintaince too required (fuel filters and such and you can change oil about three times in a gasser for the price of one change in a oil burner. If you realy are concerned about MPG you should not be looking for a big heavy truck with 36's or 37's because it will suck MPG wise gas or diesel.  

Nico, 

The Ram is coming out with a new 6.1 HEMI soon I believe.  I know it is available in other models already.  This would help with your power issues once you put the lift and tires on.  Your fenders should be fine, but you may want to add some fender flares, just for looks.  They also add some protection when it comes to rocks and brush.

Ryan

If I want to beat my truck up in the rocks and brush, I do it with a old one I have (which has thicker sheet metal too) I would not take my new truck in the rocks and brush to bang up. I have better things to do with my money.  

6.1HEMI....not so bad!anything new in prospect for diesel Cummins?

 but the torque of diesel Cummins....is great!!!

for fuel economy with big tyres is a really problem?how amount the worsening of MPG(or km/L)

the satisfaction of driving a big truck is great too!