First and foremost, thank you all for the input!!
Originally Posted by corsair23
factor aside, how long would it take you to recoup the investment based on the gas savings?
I don't DD my 40...Actually I rarely drive my 40
- Is the 40 your DD?
I guess what I'm saying is basing the decision on the fact that you will get better gas mileage might not be the best business case
If you get 10 mpg now and bump that up to 20 mpg with the conversion, and using $4/gal as the average for fuel...At 10 mpg a mile costs you $.40 vs. $.20 with a diesel. My math is probably wrong but break even doesn't come until 12,500 miles. Of course if gas stays lower than $4/gal it will take longer to pay off the cost of the conversion - @ $3.50/gal the payoff comes after about 14,300 miles...Then again if gas goes up to $5/gal the payoff comes at 10K miles. I know I'm not taking into account the price difference of gas vs. diesel so that would play in there a bit.
Now if the 5.7L V8 dies and you need to replace the engine anyway
I agree, the return on investment will bee a while. I will be able to sell the 5.7 ready to drop into another project fairly easily which will help.
Wow, that thread is big!! lot's of information.. I did do a couple of searches on CL and e-bay, it seems that the isuzu motor is quite pricey as well, if you can find a newer one with lower miles the price jumps way up. The MB 300td seems to be VERY available and affordable. I found one with 144k and can pick it up for $850.00, the rebuild cost of the 300td is high and some recommend that it is better to buy a used one OEM built rather than rebuilding one. The 300td is a car diesel and it has PS, Air cond, and other options that some of these industrial motors do not have on them as well.
Originally Posted by art hog
My 4BT in my 55 gets about 24-mpg driving from Rollinsville to Boulder on average. On the hwy it is closer to 30-mpg. I have plenty of power. You will not get that kind of mileage with a 4sp. You need an overdrive. I have a NV4500. You will also need to do a spring over and switch to FJ60 axles or mod the oil pan. There is a 3.3 cummins that is very nice but $$$$$$. Also from what I understand to run biofuels, ie: veggie oil you will need an aluminum fuel tank. Steel creates a scale on the inside of the tank and flakes off and messes everything up. So I have been told. I would go with the 300-td.
Thanks for the info!! I did not know that about biofule. Is the 4BT itself that tall or does the turbo extend up so high that you have to mount it lower in the frame?
Originally Posted by Woodsman
You can't always justify dropping a diesel into an older rig with just fuel numbers. You get the benefits or better low-end power, more mileage per tank and you'll be able to do many trail runs without taking any extra fuel where you may have taken 5-10 extra in gas.
When dealing with a new vehicle, IMO, it is very easy to justify the extra purchase price (if you have that kind of extra changing in your piggy back) because the "diesel option" is generally about how much more the vehicle will be worth even when used. In other words, you'll get your money back.
Of course, you could also be a dork like my cousin and sink over $24K in your Cummins for pulling at the county fairs. Of course, he's almost 27 and still living with mom and dad.
As far as value goes I think so too, I have owned several diesels including heavy equipment and they really hold their value as long as you take care of them.