03' Big Red

I’ve been reading this post with tons of interest since I am considering a swap to the 750 DRD in my 03 RD 688S tri axle dump how do these trucks perform off road compared to a similarly equipped truck with a 8LL ? my truck has the 8LL and 4.42:1 ratio, I realize this would limit my top end speed, most of my work is local stone delivery and site work with a little highway driving and most of that in a 55 mph speed zone. I did reflash my ECM with the AMI 370 software that moves my max rpm from 1950 up to 2150 However I’m not sure I want to run down the road at 2100 rpm to run 55 ish mph also thought about the auxiliary trans route to get overdrive but was told I would have issue shifting that since I wouldn’t have a clutch. i am looking to you guys for some real world experience to help with making the leap.

good morning people how would one go about calculating startabilty with a automatic transmission? i have heard that 60% is the minimum

What are the differences in the crdpc92 and the crdp202 ? would 46000 lb rears fit in 44000 lb housings ? Just curious....

Just looking for the best combo, probably go with the Eaton 9 LL

My trans is scheduled for replacement in the future,what would be involved in a Mack trans ?

I have a 03 RD, I recently had my local Mack Dealer change software and turbo to the AMI 370 wow what a diderence she pulls from about 1200 to 2150 every gear. It has the Eaton 8LL and 4:42 gears and 24.5 tires. is there a transmission that would be better suited for this combo ? i really like the idea of the 5 speeds used in the 70's and 80's !! although my 4:42 ratio wouldn't work so well with that trans

I have heard that one could reverse the two top gears on a Eaton 13 speed to make this a double over drive.. Anyone have any input on this ?

Yeah, I wasn't sure if I would have programming issues with the HDSeries versus the fully electronic versions.

I have a 2003 rd with a Eaton 8ll and 4:42 axle ratio i am considering swapping in a Allison automatic, I know using the 4000 series would be very costly due to wiring and computers, any thoughts on using the HD750 ? i know it's direct drive and I would have to change axle ratio to get any road speed, does the computer in my truck care what trans is used ? Or is it stand alone ? how do I determine the grade ability of this combo ? I know there are many different torque converters available. I've read I should try for 60% grade ability.

I have 2003 RD688S with a AI 350, is this considered a econodyne ? Can I reflash the ECM to a Maxidyne? I would surely enjoy the extra rpm's i have installed the super flow injectors which made a huge difference, I haven't done any software updates yet.

I checked the build date on my truck 4/03

ii was talking about a heavy spec tractor that i could use for a tandem axle dump, we max out at 58400 on a tandem here in PA trying to get a idea what kind of lite weight such a creature may have.

Hey folks Anyone have a idea what a 1989 R model tandem axle with 18/44 axles,single frame and a 8LL might weigh ?

i have thought about going the pained hood route...

i have 2003 RD688S and would like to put a older style hood on from a 80's model RD688S, i like the old school looks and wonder how mnuch work it would be..

Name: Mack RD688S (2003) Date Added: 28 February 2015 - 02:36 PM Owner: 03' Big Red Short Description: tri axle dumptruck View Vehicle

i have always found that to be a tire issue on my truck..

i did check the tag on the motor it is the AI 350, but it is also a 2003, maybe it was built late in the model year and got the 2004 engine .... if i understand correctly tha AI/AC started in the 2004 model year.

i have read about using the cruise control switches, what is the process for that ?

hey guys i need some help here. i have a 2003 RD688S with the AI 350, i had a problem with poor throttle response and no power after 1800 RPM, i had a local shop check fuel pres, it was low so they put a new pump on and they also adjusted the valves. the truck ran much better for a bit. the last couple of days though it's been a real dog, at 1800RPM it's flat..no power at all but after a storm rolled through today and cooled things off the truck run's 100% better, it would pull through 2100RPM. all the filters are new and the engine speed sensor has been replaced. it seems to me that there is bad sensor somewhere. the electronic malfunction light comes on very sporadically, maybe once a month, more or less. i haven't had the codes scannned thought. is there a way for me to scan the codes without a scanner ? i now know that air tempature makes a huge difference on performance. thanks for any input.

crap, well that didn't last long biggest POS i ever bought, shoulda kept my '88 Diamond Reo

here is a update, i had the valves adjusted and a new fuel pump installed, it's a completley different truck. I have Lesher Mack in Lebanon Pa checking as to how much Horsepower they can put into the ECM without changing turbo and injectors. the least I'll do is have the 12B installed.

here is another link to Duncannon FD in Pennsylvania, they have a 2006 Granite with a KME body. http://www.duncannonfire.com/apparatusPage.php?5

here is a link to W W engine ans Supply, they are Mack dealers and the Harrisburg, Pa location also is a KME dealer ( Kmart mobile equipment ) they should be able to get you a Mack chassis/KME body unit http://www.wwengine.com/