transmission and Rear end

[Daffit]

Have 97 2500 with auto transmission and 4:10 rear in. Pull a 26ft 5th wheel. Am worried about the transmission when pulling. To have any kind of speed must stay in overdrive. Have installed a TST power kit. Am thinking of changing rear end to 3:50 gears so can pull without overdrive but be able to drive faster than 50-60 MPH. But before doing was wondering if anyone might have better suggestions.

 

[C Schomer]

With 245 tires, mine is redlined at 70mph in direct. I think 285 tires would get you close to the same thing as a 3. 54 diff. Craig

------------------
97 3/4Ton, 2WD, 5SP, #11 Plate, AFC kit, 14 Housing, AF942M Air filter, Gutted Cat, 4"From Turbo, Airlift, Shortened Frame, Custom Bed, HEY FORDBOY POWERSTROKE THIS!

 

[Dieselnerd]

Don't worry about driving in OD. I pull a much larger trailer with a TST 230/605 and it rarely comes out of OD. Just keep the RPM's over 2000 to keep the pressures up or install a BD Pressure Loc. Keep the 4:10's for the day you get a big fifth wheel. This is actually a pretty strong transmission.

------------------
Ron

'96 Club Cab 2500 4x4, 4:10LS, Camper/Tow package, Auto, BD Pressure Loc, Mystery Switch, TST 230/605, Cat Test Pipe, Cummins Chrome, Mag-Hytec rear and trans covers, Boost, Pyro and trans gauges, Optima Red Tops, All black. Tow 14k HitchHiker triple glide 5th Wheel. Also use 9. 5' Lance camper. NRA Life Member.

 

[Cooker]

Dieselnerd is right about the line pressure. OD is ok if the transmission pressures are maintained.

Personally I'd rather have 4. 10's, but I'd also like to run 35" tires. You could put on a larger tire to raise your effective gear ratio. 285's will change your effective gearing to about 3. 73 if you are switching from stock 245's.

IMO if you are going to stay with 245's or maybe 265's the 3. 54 would be a better rear end. Our 12v produce a lot of power below 2000rpm. You might also consider a over/underdive unit, this way you can have the best of both worlds.

You best bet, and least expensive, may be to try larger tires. Ryan

 

[Daffit]

Thanks for the info. I have already changed my tires to 285s. Helped a little but was worried about OD. What is a BD Pressure loc.

 

[Dak - BD Power]

PressureLoc is a bolt on device that increases lockup clutch holding pressure by about 30 psi when TCC is in lock up.

Check out www.bd-power.com for more info.

------------------
Real BOMBers never get speeding tickets. . just a lot of warnings!

 

[wbrown02]

Have you given any thought to an overdrive. I have the GearVendor behind my 5 speed and wouldn't be without one. Running empty it has increaded the fuel mileage by at least 4 mpg and besides is great in the mountains.

------------------
95 Ram 3500 Reg Cab Dually,5 speed,Gear Vendor,TST 235/605, Jannetty 4"exhaust,Psycoty K&N 880,Prime Loc, Pac Brake,Valentine One, Full Gauges..... ect... . ect

 

[QRTRHRS]

The general consensus is to avoid low (<1700)rpm's in 5th gear. The vibration resulting from lugging is what loosens up the fifth gear nut. Happy camping!