Off Roading 44's and Gears????????

[JBurghard]

I am looking at putting 44's on my first Gen and wanted to know if anyone else has put tires this large on a firrst gen.....



I currently haven't lifted the truck yet so I was trying to figure out what I would have to do to make them work... ... I wanna keep the overall height of my truck as low as possible to keep the CG from getting to high... ... . I am willing to trim sheet metal as well as lift the truck... Also I am currently looking into putting a flatbed on it which would give me all kinds of clearence in the back...



Also I was wondering what gears I should run with 44's and what would that do to my fuel milage??????



Any help on this would be appreciated.



Thanks

James

 

[NVR FNSH]

Originally posted by JBurghard

Also I was wondering what gears I should run with 44's and what would that do to my fuel milage??????

You're kidding right? 44s and you're worried about fuel mileage?



Sorry I can't offer any advice on how much lift or the gears.



Brian

 

[Patriot Diesel]

Originally posted by JBurghard

I am looking at putting 44's on my first Gen and wanted to know if anyone else has put tires this large on a firrst gen.....



I currently haven't lifted the truck yet so I was trying to figure out what I would have to do to make them work... ... I wanna keep the overall height of my truck as low as possible to keep the CG from getting to high... ... . I am willing to trim sheet metal as well as lift the truck... Also I am currently looking into putting a flatbed on it which would give me all kinds of clearence in the back...



Also I was wondering what gears I should run with 44's and what would that do to my fuel milage??????



Any help on this would be appreciated.



Thanks

James

I would go check out www.pavementsucks.com , lots of guys on there running 44's. I would think that you would want 5. 13's or 5. 29's, whichever your axles are compatible with...

 

[Coalsmoke]

when you go that big, you don't care about fuel milage

 

[JBurghard]

Its not that I care that much... . but...



I dont wanna get 2 mpg... .



If you are talking like 10 or better then I could care less

 

[Coalsmoke]

My best guess would be that you would land yourself close to the 12mpg range.

 

[XJSuperman]

Just figure out where your current normal driving RPM range is and use the formula to determine which gear ratio will get you closest to stock... then if it were me I would go one ratio deeper in order to accomodate the MUCH higher weight of the 44's.





Formula is as follows:





(Engine RPM's * tire diameter)

______________________________________________

(336 * t-case ratio * transmission ratio * differential ratio) = MPH





t-case ratio is of course 1:1 in high range and then use the ratio for whatever transmission gear you are in to determine MPH

 

[914x4ctd]

You better invest in a croosover steering system and put some steel on the frame around the steering box. and a panhard rod. I have ridden in several trucks with large tires on them it is not as fun as it looks. You will also need rear discs to stop it. If I remember right I think there is either a 5:13 gear or a 5:29 gear avail. Forget milage. It is like towing when driving unloaded.

 

[JBurghard]

I have decided to go with 37's for now as well as 4. 10's.....



I have a friend machining parts for the Crossover Steering and plan on us Hydro Steering to help out... .



Also currently trying to figure out what transfer case to use or what kind of setup to run...



Getrag has 29 spline output which is killing my options..... And I can't affoard a NV4500 conversion...



Thanks again for the input

 

[Mopar_Mudder]

Even though you have decided alreadt some thoughts.



You don't want to drive a truck with 44's down the road, not only is it hard to drive but you are just callin for cops.



40 is as big as I would go and expect to drive it down the road.



For thoose 37's you are going to need a 4" suspension lift and a 3" body lift along with some fender trimming in order to clear them. Cross over is a good thing but not totaly needed if you keep to the 4" suspension lift.



For gears with the 37's I would go in the 4. 88 area



Their are some pictures of my cross over in this bunch:



Cross Over & 4 link

 

[JBurghard]

I have come to the same conclusion about not going over 40's... .



As far as the gear ratio when you use the formula it tells me to go from the 3. 54's to 4. 10's..... so why do you say 4. 88?????



As far as fitting goes..... There is going to be a flatbed on the back... and the front is getting major fender work... like about 10 inches worth of triming and I am working on a shackle flip to get me the extra 4 inches and the crossover should be done in the next couple of weeks.



I will post pics once she is done



James

 

[Excessive Force]

I ran 44's on an '81 Chevy,and ran 4. 56 gears. I realize you have a Cummins,but the info may help. I ran a 383 stroker w/a B&M blower. I had 15" of lift,and it rode like a lumber wagon. . In order to make the front shaft work i had to use a divorced NP205 transfer case. It was pretty cool to drive,and would do 100 mph no problem !!

 

[Mopar_Mudder]

Well gears are tricky, you are running a diesel so you can get away with a little higher gear, the manual transmission also helps you out in that area.



It is not just a mater of making up for the large diameter of the tire. You also have alot more weight of tire to through around. It actually take more gear to make up for the heavier wider tires and equal the same "power" to the ground.



Your intended use makes a big difference also



I ran 4. 88's with my 38. 5's in my truck. This is with a 440 that is around 500 hp. It was a very good match with the 38. 5's



Now I am running 39. 5x18 Boggers and even though they are only 1" taller they made a huge differnce in power. Not so much do to the weight of the tire but the weight of all the crap they can dig and through. I also then switched from a 4 speed to a 727 auto which hurt some more. So now I have gone to 5. 86 gears to get back to the same feel that I had with my 38. 5's and 4. 88 gears.



What trans case you pick also makes a huge differnce. I run NP205's which are super strong but only gears 1. 96:1 in low range. That compared to most other trans cases that run in the 2. 40:1 area, that makes a big differnce.



Lots of factors in it, a never ending building process. Oh ya, if you got lockers that takes more power and gear also. Have fun.

 

[jayhawktrailers.com]

If you need stuff for the crossover call Scott at rockstomper. He's just down the road from you in Firestone CO 303-833-1431. He also does some hydraulic assist stuff that turned out great on my buddies Scout ( which is getting a 4bt )

 

[jayhawktrailers.com]

btw I couldn't get into the classifieds to place an add. Is anyone needing a set of axles out of a 1990 Dodge with diesel. my buddy wants to sell the pair for 1500. 00. Woul appreciate the info on how to set up to post in the classifieds.