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http://dodgeram.org/tech/specs/wheel/specs.htm
Rim Backspacing and Wheel Offset
Offset: measurement of the wheel's centerline in relationship to your hub flange. Zero offset puts the hub flange at the center of the rim. Negative offset moves the rim out away from the vehicle and causes more of the more the wheel to stick out from under the truck. Positive offset moves the tire and wheel toward the vehicle.
Backspacing: The distance from the hub to the back of the rim. This determines with how far the tire reaches into the wheelwell. If you get wide wheels and keep stock offset, the wheel will increase backspace toward the inside. If you want to keep stock backspacing, then you need a lot of offset (NOT desirable).
A wide wheel, with less backspacing puts extra stress on the bearings and seals, etc, etc because the center of the tire is farther away from the hub. A wide wheel with less backspacing can also cause more rubbing on the control arms and a reduced turning radius.
Ram Rim Dimensions
1994-1999 1500 2WD/4WD Aluminum Wheels
* Lug Pattern - 5 on 5.5", 1/2" bolt
* Rim Size - 16x7.0"
* Offset - +13.97mm
* Backspace - 5"
* Max Tire Size -
* 15x8.0 rims with 3.5" backspace will fit, but they stick out of the wheel wells.
2000-2001 1500 2WD/4WD 16" Aluminum Wheels
* not posted yet
2000-2003 1500 2WD/4WD 17" Steel Wheels (Chrome or painted)
* Lug Pattern: 5 on 5 1/2
* Rim Size: 17x7"
* Fits 94 and up 1500 trucks
2000-2003 1500 2WD/4WD 17" Aluminum Wheels (posted to DiRT by Mat Felthousen):
* Lug Pattern: 5 on 5 1/2
* Weight: 23.5 pounds
* Rim Size: 17x8"
* Actual width edge to edge: 9 1/16"
* Backspacing: 5 9/16".�
* The space from the outside edge to the mounting surface (against the rotor) is 3 1/2".
* offset calculate: 1 1/32"
* Fits 94 and up 1500 trucks
1994-2002 2500 2WD/4WD Steel Wheels:
* Lug Pattern - 8 on 6.5", 9/16" bolt
* Rim Size - 16x6.5"
* Offset - 4.75"
* Max Tire Size - 245/75R16, 255/85R16
2000-2002 2500 2WD/4WD Forged Aluminum Wheels:
* Lug Pattern - 8 on 6.5", 9/16" bolt
* Rim Size - 16x8"
* Offset - 6.25"
* Max Tire Size - ??
* Notes from Mike Cash, who installed them on his 1999 2500 4X4 with a V10: These wheels will not easily fit older Rams because the brake drums and steering components will not clear the rim.
o Rear: Have a machine shop turn the widest part of the brake drum down by about 1/8.
o Front: If clearance is a problem, grind the steering components just enough to clear the wheel rim. The tie rod ends may need to be lightly touched with a peanut grinder. Make sure the front wheels are pushed all the way back to the rotor, or you could cinch up the lugs and bind the wheel in a bind/angle= wobbly wheel. It is a very close tolerance at the center circle in the wheel in front, but the wheels will fit.
Aftermarket Rims
Some 15" wheels will not clear the brake calipers and/or tie rod ends. Light grinding on the calipers may be need to gain clearance.
Subject: [RAM] Rim for Rams
Date: Fri, 16 Jan 1998 08:19:06 -0500 (EST)
From: Chris_Siano@iacnet.com
To: ramtruck
> I'm thinking about getting a Ram 2500. If I get the Dana 60 and
> Dana 70 combo would I have problems using deep dish rims,
> the rims will probably be 10-12"?
I'm not sure what you are asking.
Rims should maintain the same centerline no matter the size. This means that if the offset is 2", it MUST remain 2". In other words, if the backspace = 4" on a 6" rim, you will need 5" on an 8" rim.
While this is the ideal, it isn't always possible. (There is only so much room to the inside of the wheelwell.)
So, you try to get as close as possible. The Rams seem to do well with a backspace in the 4-5" range in terms of fit. While this is close to optimum for an 8" rim, it starts to place more and more stress as the width rises. A 10" rim would most likely be perfectly fine in all respects. However, a 12" (and the tire that would carry) is starting to place the centerline of the wheel beyond the bearings.
It's up to you if you want to go that large, but I wouldn't expect to be able to use the truck to it's limits without doing damage. If you're just driving it around empty on the road, it should be fine, but add a trailer or large load, and you are adding stress the bearings were not designed to handle. They might do just fine, but it is a gamble.
---------------
Part Number for 2001-2002 Alloy 3500 wheels: 52106367AA
the RamHack thinks that 10" is the largest you should go if you use the truck hard.
Lug Nut Torque Specs
Subject: Re: [RAM] Lug nut torque specs
Date: Sun, 8 Feb 1998 01:11:44 EST
From: Drdonnelly@aol.com
To: ramtruck
torque spec for 2500 wheels is 135 ft LB dry. I use grease and 115 ft lb.
Joe
---
My '94 SERVICE MANUAL SAYS:
* 80-110 ft lbs (108-150 Nm) on 5 stud wheels
* 120-150 ft lbs (163-203 NM) on 8 stud single wheels
* 130-160 ft lbs (176-217 NM) on 8 stud dual wheels
I always use Never-Seez on my wheel studs.
Subject: Re: [RAM] Speedometer calibration...
Date: Wed, 1 Apr 1998 01:07:53 EST
From: Drdonnelly <Drdonnelly@aol.com>
To: ramtruck
the part number is 520676XX for the speedo gear, where XX is the number of teeth. If you have 31 teeth, like for 245-75-16 tires and 3.54 gears, it would be 52067631. The part number series available up to 38 teeth.
--
Subject: Changing tire size
Date: Fri, 13 Mar 98 20:53:20 CST
From: "Fest3er" <murphyn@mc.net>
To: cummins
Stopped at my Friendly Dodge Dealer this morning on the way to work and inquired about the procedure for programming the CAB. He looked in the service manual, looked in a couple others and finally dragged out the Chassis Diagnostic Manual. There, in section 29A, it explains the procedure needed to program the CAB for specific tire sizes. [The CAB sends a pulse stream to the PCM, which drives the speedo/odo; to change the calibration, the CAB needs to be told, among other things, the number of teeth on the RWAL sense ring and the rev/mi of the installed tires.]
So, if you change your tire size and your dealer hasn't a clue as to correcting the speed/odo, point him to the Chassis Diagnostic Manual, section 29A. It's all there.
Fest3er
NOTE: the 98 1/2 models do not use speedometer gears and the speed metering is taken from the ABS sensors. To change "gears" for different tire sizes requires reprogramming of the PCM. Dealers have been having problems with this procedure, and many axle ratio/tire size combinations are not available.
Rim Backspacing and Wheel Offset
Offset: measurement of the wheel's centerline in relationship to your hub flange. Zero offset puts the hub flange at the center of the rim. Negative offset moves the rim out away from the vehicle and causes more of the more the wheel to stick out from under the truck. Positive offset moves the tire and wheel toward the vehicle.
Backspacing: The distance from the hub to the back of the rim. This determines with how far the tire reaches into the wheelwell. If you get wide wheels and keep stock offset, the wheel will increase backspace toward the inside. If you want to keep stock backspacing, then you need a lot of offset (NOT desirable).
A wide wheel, with less backspacing puts extra stress on the bearings and seals, etc, etc because the center of the tire is farther away from the hub. A wide wheel with less backspacing can also cause more rubbing on the control arms and a reduced turning radius.
Ram Rim Dimensions
1994-1999 1500 2WD/4WD Aluminum Wheels
* Lug Pattern - 5 on 5.5", 1/2" bolt
* Rim Size - 16x7.0"
* Offset - +13.97mm
* Backspace - 5"
* Max Tire Size -
* 15x8.0 rims with 3.5" backspace will fit, but they stick out of the wheel wells.
2000-2001 1500 2WD/4WD 16" Aluminum Wheels
* not posted yet
2000-2003 1500 2WD/4WD 17" Steel Wheels (Chrome or painted)
* Lug Pattern: 5 on 5 1/2
* Rim Size: 17x7"
* Fits 94 and up 1500 trucks
2000-2003 1500 2WD/4WD 17" Aluminum Wheels (posted to DiRT by Mat Felthousen):
* Lug Pattern: 5 on 5 1/2
* Weight: 23.5 pounds
* Rim Size: 17x8"
* Actual width edge to edge: 9 1/16"
* Backspacing: 5 9/16".�
* The space from the outside edge to the mounting surface (against the rotor) is 3 1/2".
* offset calculate: 1 1/32"
* Fits 94 and up 1500 trucks
1994-2002 2500 2WD/4WD Steel Wheels:
* Lug Pattern - 8 on 6.5", 9/16" bolt
* Rim Size - 16x6.5"
* Offset - 4.75"
* Max Tire Size - 245/75R16, 255/85R16
2000-2002 2500 2WD/4WD Forged Aluminum Wheels:
* Lug Pattern - 8 on 6.5", 9/16" bolt
* Rim Size - 16x8"
* Offset - 6.25"
* Max Tire Size - ??
* Notes from Mike Cash, who installed them on his 1999 2500 4X4 with a V10: These wheels will not easily fit older Rams because the brake drums and steering components will not clear the rim.
o Rear: Have a machine shop turn the widest part of the brake drum down by about 1/8.
o Front: If clearance is a problem, grind the steering components just enough to clear the wheel rim. The tie rod ends may need to be lightly touched with a peanut grinder. Make sure the front wheels are pushed all the way back to the rotor, or you could cinch up the lugs and bind the wheel in a bind/angle= wobbly wheel. It is a very close tolerance at the center circle in the wheel in front, but the wheels will fit.
Aftermarket Rims
Some 15" wheels will not clear the brake calipers and/or tie rod ends. Light grinding on the calipers may be need to gain clearance.
Subject: [RAM] Rim for Rams
Date: Fri, 16 Jan 1998 08:19:06 -0500 (EST)
From: Chris_Siano@iacnet.com
To: ramtruck
> I'm thinking about getting a Ram 2500. If I get the Dana 60 and
> Dana 70 combo would I have problems using deep dish rims,
> the rims will probably be 10-12"?
I'm not sure what you are asking.
Rims should maintain the same centerline no matter the size. This means that if the offset is 2", it MUST remain 2". In other words, if the backspace = 4" on a 6" rim, you will need 5" on an 8" rim.
While this is the ideal, it isn't always possible. (There is only so much room to the inside of the wheelwell.)
So, you try to get as close as possible. The Rams seem to do well with a backspace in the 4-5" range in terms of fit. While this is close to optimum for an 8" rim, it starts to place more and more stress as the width rises. A 10" rim would most likely be perfectly fine in all respects. However, a 12" (and the tire that would carry) is starting to place the centerline of the wheel beyond the bearings.
It's up to you if you want to go that large, but I wouldn't expect to be able to use the truck to it's limits without doing damage. If you're just driving it around empty on the road, it should be fine, but add a trailer or large load, and you are adding stress the bearings were not designed to handle. They might do just fine, but it is a gamble.
---------------
Part Number for 2001-2002 Alloy 3500 wheels: 52106367AA
the RamHack thinks that 10" is the largest you should go if you use the truck hard.
Lug Nut Torque Specs
Subject: Re: [RAM] Lug nut torque specs
Date: Sun, 8 Feb 1998 01:11:44 EST
From: Drdonnelly@aol.com
To: ramtruck
torque spec for 2500 wheels is 135 ft LB dry. I use grease and 115 ft lb.
Joe
---
My '94 SERVICE MANUAL SAYS:
* 80-110 ft lbs (108-150 Nm) on 5 stud wheels
* 120-150 ft lbs (163-203 NM) on 8 stud single wheels
* 130-160 ft lbs (176-217 NM) on 8 stud dual wheels
I always use Never-Seez on my wheel studs.
Subject: Re: [RAM] Speedometer calibration...
Date: Wed, 1 Apr 1998 01:07:53 EST
From: Drdonnelly <Drdonnelly@aol.com>
To: ramtruck
the part number is 520676XX for the speedo gear, where XX is the number of teeth. If you have 31 teeth, like for 245-75-16 tires and 3.54 gears, it would be 52067631. The part number series available up to 38 teeth.
--
Subject: Changing tire size
Date: Fri, 13 Mar 98 20:53:20 CST
From: "Fest3er" <murphyn@mc.net>
To: cummins
Stopped at my Friendly Dodge Dealer this morning on the way to work and inquired about the procedure for programming the CAB. He looked in the service manual, looked in a couple others and finally dragged out the Chassis Diagnostic Manual. There, in section 29A, it explains the procedure needed to program the CAB for specific tire sizes. [The CAB sends a pulse stream to the PCM, which drives the speedo/odo; to change the calibration, the CAB needs to be told, among other things, the number of teeth on the RWAL sense ring and the rev/mi of the installed tires.]
So, if you change your tire size and your dealer hasn't a clue as to correcting the speed/odo, point him to the Chassis Diagnostic Manual, section 29A. It's all there.
Fest3er
NOTE: the 98 1/2 models do not use speedometer gears and the speed metering is taken from the ABS sensors. To change "gears" for different tire sizes requires reprogramming of the PCM. Dealers have been having problems with this procedure, and many axle ratio/tire size combinations are not available.
