I really enjoy drag racing, but I feel I'm pretty close to the limit of what I can do with my truck. I have to admit Im getting concerned racing my DD and putting it at risk.
Ive been toying around with an idea for a long while, and if funds allow, Im going to do it. Id love to find a 1/2ton 2wd Reg Cab shortbox and transfer my 2500hd drivetrain over, stock turbo and all. All the aftermarket parts I currently own would swap over, too. I figure this will put about the same amounts of stress on the engine/trans that I currently do now, but with lots of room to improve later on. I figure the weight savings alone would net me a low 11 truck with little effort. Heck, Trent's S475/stocker twins would make it a veryyy interesting truck.
I figure 1999-2002 trucks are getting down around $2-3K, and by the time I get around to do this swap, 2003-2004 trucks should be that cheap too. Id prefer to find a 2003-04 GMC. This is mainly because I hate the cat-eye Chevy, but if one fell into my lap, Id find a junkyard to trade front clips to an early Chevy look.
I would obviously have to find a wrecked LLY or LBZ (prefer the LBZ) so I could put that drivetrain into my DD. I figure this cost to be somewhere around $5K. With an LBZ, I figure on top of getting the 6spd trans and IMO a more reliable Dmax, I would get all the small parts that one of these swaps need, and it also solves any future LB7 injector problem Id have with my DD. Since I plan on driving my truck til the wheels fall off, I win both ways.
So this is what Ive found about a 1500/Dmax swap so far:
1) Drivetrain would swap rather easy physically. If I used a 1999-2002 truck, Id have to procure the appropriate motor/trans wiring harness as my engine is a 2003. That wouldnt be all that tough to find, but like stated, Id prefer to find a 2003-04 truck so the swap would be straight up. Motor mounts arent an issue, as Id use 2500hd frame pads. I also wouldnt have a front pumpkin to have to work around. Only trouble I may have is the huge front crossmember on the 2wd 1500 trucks that may get in the way, and I may have to notch the stamped crossmember behind the K-member to fit the oil pan.
2) Id use MikeL's crossmember for the trans to keep things up and out of the way. The Allison does NOT need the 2" body lift (more on that later) to fit. Already tested that a few years ago, and found you can fit your hand up around the trans without the body lift.
The 11.5 AAM axle will be a straight swap, too....at least according to what I read on GMUpfitter. Custom driveshaft would not be tough for a shop to make.
I think Id contact Tony B for a front Ujoint shield/driveshaft loop.
3) Suspension. Front suspension on the 1500s is coil spring. The extra weight of the Dmax will sag those springs pretty quick,esp if the original drivetrain is a V6/4L60. This may be good, it may not. I would want to lower the truck anyway, but not at the expense of having a "weak" front suspension that will "jump" on launch. I may have to use a lowering kit with higher-rate front springs to get the ideal balance. Obviously Id have to use adjustable shocks like the QA1s I have now. Rack and pinion steering is a plus because I wouldnt need sleeves or braces. Toughest part will be connecting the lines from the rack to the Dmax PS pump.
I have not formulated my rear suspension setup, other than to use the 1500 springs, my Caltracs, adjustable shocks, and then use a LOT of Trent's ideas on suspension setup. I may have to use drop shackles to get the height I need in the rear. Heck, I may find my pinion snubber idea would work here. In the end, I figure most common suspension ideas that racers use will work for this truck.
4) Brakes. Hmm. Found that EBC (among others) makes a simple 14" rotor swap for the 1500 trucks. OR I could just swap 2500 spindles and brakes over, depending on the balljoints. The recent DieselWorld article on the Dmax Tahoe leads me to believe its a relatively simple swap. Id prefer to run 8-lug wheels on the front to match the rear, but if i cant, I cant. Stock 2500HD rear brakes are more than adequate. Hydroboost is literally drilling one hole to fit it in a 1500 truck, possibly swapping brake pedal assemblies. Braided lines would also be swapped for old rubber. Also, the throttle pedal would be a relatively easy swap.
5) Cooling stack. Ok, one toughy. The 2" body lift is needed here for the cooling stack to fit properly..thats the only reason its there. BUT, I really dont want to lift the body and screw up anything. So, I have to start doing some research and see if itd be possible to use a 2500hd core support and lower it into the 1500 frame, either by using thinner front body mounts (drilling new mount holes in the support doesnt scare me) or notching the frame itself. I dont see that pockets cut into the front frame ahead of the engine would hurt anything, as long as I take the cut pieces, reverse them and weld them back in to make the pocket. According to info I read from TDIguy, the lower radiator hose may have an issue next to the frame, so that will have to be addressed, and the I/C hookups will have to be scrutinized. Again, if I drop the HD stack down in adn find that the pipes will hit the frame, then I'll have to lift the front and deal with the rake by way of the suspension...maybe drop knuckles. Electric fans would be used for cooling, so no worries about the fan. A/C would magically disappear, so Id have all the extra room that would provide. A MikeL trans cooler would also be used.
6) Fuel system. Stock fuel tank would say goodbye. My thinking is to use a fuel cell in the bed (mounted straddling the rear axle to "neutral its weight"), and mount my FASS pump/filter on a stand in front of it. 1/2" fuel line would be run from there, along with the 3/8" return line. I think I could even use the 2500hd fuel cooler on the return if I leave the bed exposed.
7) Intake/Exhaust. Id use my S&B intake off my current truck. Id probably run a stack (ugh) thru the bed, even though Im not thrilled about them.
8) Interior/Body. Use a racing seat/5 pt harness. No pass seat. Interior would otherwise remain stock. Gauges from my truck would move over to this one. Body would get interesting. In my mind's eye, I see using a Quadrasteer box to get the slightly wider wheel wells, so I can fit larger tires underneath...well, plus the "unique" factor to it. I think the plastic box could also save me some weight. I was also thinking I would run a hard plastic cover on the box as well, but leaving the bed open with no tailgate could work too. A roll pan would be used, too. I also figure that the frame will probably have to be strengthened by boxing or with gussets.
9) Weight savings. From all my research, a stock worktruck 1500 RC/SB 2wd has a curb weight of around 3600lbs. Im talking a crank windows/barebones truck. Figure a Dmax drivetrain would add about 800lbs total over a comparable gas V8 setup. If I have to strngthen the frame, that will add more weight. I could save weight by removing all the "normal" things like what I do now, plus the AC parts and the OEM seats. Battery would stay in its OEM location unless I need to move it for weight transfer. I figure even with a rollbar, It'd be somewhere around 4500 lbs with me in the truck.
With all that being said, I still have some things I havent worked out yet.
I still have to figure out what tires to run. I have a pair of Centerline 16x8 wheels sitting in the garage for the rears. I figure the 12"x16" M&H slicks will work perfect there. I havent been able to find a decent front tire to match, though. No way do I want to be like that guy in the Dodge a couple years ago, mixing radials and biasply.
Rollbar will also be a concern. From what Ive read at the NHRA website, I need a 6-pt bar? A 4-pt would have worked perfect, but I doubt it'd be legal now. If I need a 6-pt, I'll have to figure out what to do with the trailing arms.
So tell me what you think. Am I nuts? Back in 1990, I swapped a 455 Olds into a Fox-body Mustang, so I've done something like this before. (Hey....its what I had!)
Ive been toying around with an idea for a long while, and if funds allow, Im going to do it. Id love to find a 1/2ton 2wd Reg Cab shortbox and transfer my 2500hd drivetrain over, stock turbo and all. All the aftermarket parts I currently own would swap over, too. I figure this will put about the same amounts of stress on the engine/trans that I currently do now, but with lots of room to improve later on. I figure the weight savings alone would net me a low 11 truck with little effort. Heck, Trent's S475/stocker twins would make it a veryyy interesting truck.
I figure 1999-2002 trucks are getting down around $2-3K, and by the time I get around to do this swap, 2003-2004 trucks should be that cheap too. Id prefer to find a 2003-04 GMC. This is mainly because I hate the cat-eye Chevy, but if one fell into my lap, Id find a junkyard to trade front clips to an early Chevy look.
I would obviously have to find a wrecked LLY or LBZ (prefer the LBZ) so I could put that drivetrain into my DD. I figure this cost to be somewhere around $5K. With an LBZ, I figure on top of getting the 6spd trans and IMO a more reliable Dmax, I would get all the small parts that one of these swaps need, and it also solves any future LB7 injector problem Id have with my DD. Since I plan on driving my truck til the wheels fall off, I win both ways.
So this is what Ive found about a 1500/Dmax swap so far:
1) Drivetrain would swap rather easy physically. If I used a 1999-2002 truck, Id have to procure the appropriate motor/trans wiring harness as my engine is a 2003. That wouldnt be all that tough to find, but like stated, Id prefer to find a 2003-04 truck so the swap would be straight up. Motor mounts arent an issue, as Id use 2500hd frame pads. I also wouldnt have a front pumpkin to have to work around. Only trouble I may have is the huge front crossmember on the 2wd 1500 trucks that may get in the way, and I may have to notch the stamped crossmember behind the K-member to fit the oil pan.
2) Id use MikeL's crossmember for the trans to keep things up and out of the way. The Allison does NOT need the 2" body lift (more on that later) to fit. Already tested that a few years ago, and found you can fit your hand up around the trans without the body lift.
The 11.5 AAM axle will be a straight swap, too....at least according to what I read on GMUpfitter. Custom driveshaft would not be tough for a shop to make.
I think Id contact Tony B for a front Ujoint shield/driveshaft loop.
3) Suspension. Front suspension on the 1500s is coil spring. The extra weight of the Dmax will sag those springs pretty quick,esp if the original drivetrain is a V6/4L60. This may be good, it may not. I would want to lower the truck anyway, but not at the expense of having a "weak" front suspension that will "jump" on launch. I may have to use a lowering kit with higher-rate front springs to get the ideal balance. Obviously Id have to use adjustable shocks like the QA1s I have now. Rack and pinion steering is a plus because I wouldnt need sleeves or braces. Toughest part will be connecting the lines from the rack to the Dmax PS pump.
I have not formulated my rear suspension setup, other than to use the 1500 springs, my Caltracs, adjustable shocks, and then use a LOT of Trent's ideas on suspension setup. I may have to use drop shackles to get the height I need in the rear. Heck, I may find my pinion snubber idea would work here. In the end, I figure most common suspension ideas that racers use will work for this truck.
4) Brakes. Hmm. Found that EBC (among others) makes a simple 14" rotor swap for the 1500 trucks. OR I could just swap 2500 spindles and brakes over, depending on the balljoints. The recent DieselWorld article on the Dmax Tahoe leads me to believe its a relatively simple swap. Id prefer to run 8-lug wheels on the front to match the rear, but if i cant, I cant. Stock 2500HD rear brakes are more than adequate. Hydroboost is literally drilling one hole to fit it in a 1500 truck, possibly swapping brake pedal assemblies. Braided lines would also be swapped for old rubber. Also, the throttle pedal would be a relatively easy swap.
5) Cooling stack. Ok, one toughy. The 2" body lift is needed here for the cooling stack to fit properly..thats the only reason its there. BUT, I really dont want to lift the body and screw up anything. So, I have to start doing some research and see if itd be possible to use a 2500hd core support and lower it into the 1500 frame, either by using thinner front body mounts (drilling new mount holes in the support doesnt scare me) or notching the frame itself. I dont see that pockets cut into the front frame ahead of the engine would hurt anything, as long as I take the cut pieces, reverse them and weld them back in to make the pocket. According to info I read from TDIguy, the lower radiator hose may have an issue next to the frame, so that will have to be addressed, and the I/C hookups will have to be scrutinized. Again, if I drop the HD stack down in adn find that the pipes will hit the frame, then I'll have to lift the front and deal with the rake by way of the suspension...maybe drop knuckles. Electric fans would be used for cooling, so no worries about the fan. A/C would magically disappear, so Id have all the extra room that would provide. A MikeL trans cooler would also be used.
6) Fuel system. Stock fuel tank would say goodbye. My thinking is to use a fuel cell in the bed (mounted straddling the rear axle to "neutral its weight"), and mount my FASS pump/filter on a stand in front of it. 1/2" fuel line would be run from there, along with the 3/8" return line. I think I could even use the 2500hd fuel cooler on the return if I leave the bed exposed.
7) Intake/Exhaust. Id use my S&B intake off my current truck. Id probably run a stack (ugh) thru the bed, even though Im not thrilled about them.
8) Interior/Body. Use a racing seat/5 pt harness. No pass seat. Interior would otherwise remain stock. Gauges from my truck would move over to this one. Body would get interesting. In my mind's eye, I see using a Quadrasteer box to get the slightly wider wheel wells, so I can fit larger tires underneath...well, plus the "unique" factor to it. I think the plastic box could also save me some weight. I was also thinking I would run a hard plastic cover on the box as well, but leaving the bed open with no tailgate could work too. A roll pan would be used, too. I also figure that the frame will probably have to be strengthened by boxing or with gussets.
9) Weight savings. From all my research, a stock worktruck 1500 RC/SB 2wd has a curb weight of around 3600lbs. Im talking a crank windows/barebones truck. Figure a Dmax drivetrain would add about 800lbs total over a comparable gas V8 setup. If I have to strngthen the frame, that will add more weight. I could save weight by removing all the "normal" things like what I do now, plus the AC parts and the OEM seats. Battery would stay in its OEM location unless I need to move it for weight transfer. I figure even with a rollbar, It'd be somewhere around 4500 lbs with me in the truck.
With all that being said, I still have some things I havent worked out yet.
I still have to figure out what tires to run. I have a pair of Centerline 16x8 wheels sitting in the garage for the rears. I figure the 12"x16" M&H slicks will work perfect there. I havent been able to find a decent front tire to match, though. No way do I want to be like that guy in the Dodge a couple years ago, mixing radials and biasply.
Rollbar will also be a concern. From what Ive read at the NHRA website, I need a 6-pt bar? A 4-pt would have worked perfect, but I doubt it'd be legal now. If I need a 6-pt, I'll have to figure out what to do with the trailing arms.
So tell me what you think. Am I nuts? Back in 1990, I swapped a 455 Olds into a Fox-body Mustang, so I've done something like this before. (Hey....its what I had!)
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