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This is just a post for information. Saw an ad for a low miles 2000 rd690s with a seven speed. What little information I can find, not many people like the seven speed for a dump truck. Where these trucks mostly day cab trucks that were converted to dump trucks. Shows double frame,  em7 300 horsepower.  looks like a nice set up all except the seven speed. Just gaining knowledge so appreciate the information 

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the seven speed is a tough tranny.  but patience is needed to drive it. they do not shift as smooth as an Eaton and the time between gears is long.  that tranny is a 2070...  probably has 4:17 or 4:42 rears..  it's a strong combo, just slow.. I dont mind 'slow'  it's a truck..  jojo

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I don’t mind slow either jojo. I get passed all the time in my Toyota Tacoma. I’m just not in any hurry. Where I’m from we have quite a few curves so going over 50 loaded is going be average.

is this a big difference from that 9 speed T3901 I’m using now. Since I have never driven a 6 speed where is the difference. If that’s a fair question 

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the T300 is a smoother shifting tranny, with shorter gears.. as you know.  It would be cool if you had access to a 7 speed for practice to see if you like it..  When I drive them, I count in my head, 1-1000,, 2-1000, shift. I double clutch so so when I come out of gear I say 1-1000, (nuetral) 2-1000 into next gear... it's silly but it works for me,,, then after a few minutes i'm back to having a decent rhythm I still scrape a gear here and there.  The blue button on the shifter for the 7spd. is for low and low-low. you start in low-low, then go to low. if you need to use low range. then when you change the range you have to flip the blue button up as you pass through nuetral, because it is not synchronized...  like the 9 spd. you have...  

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9 minutes ago, Joey Mack said:

the T300 is a smoother shifting tranny, with shorter gears.. as you know.  It would be cool if you had access to a 7 speed for practice to see if you like it..  When I drive them, I count in my head, 1-1000,, 2-1000, shift. I double clutch so so when I come out of gear I say 1-1000, (nuetral) 2-1000 into next gear... it's silly but it works for me,,, then after a few minutes i'm back to having a decent rhythm I still scrape a gear here and there.  The blue button on the shifter for the 7spd. is for low and low-low. you start in low-low, then go to low. if you need to use low range. then when you change the range you have to flip the blue button up as you pass through nuetral, because it is not synchronized...  like the 9 spd. you have...  

I have gotten where I only use the clutch in that 9 speed to take off. It took a while but I got the hang of it. So it seems that 7 speed going to be a lot pickier than 9 speed. 

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yes, but youll get it..  I double clutch, I get grief for being a school boy driver.  well, after 24 years, i dont care..  it works for me and i can shift smoother.. however, an Eaton is easy to shift without the clutch.  it's all in youre skill set and time in the seat... no biggie, as long as you are not trashing the drive line and clutch...  jojo

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1 hour ago, Mark T said:

FYI.... that add ?   that's a real dump truck spec.  Maybe not the most glamourous , but way better than a converted tractor if it's in any kind of shape and not abused or neglected 

I understand now. Education is not free and I really had no idea how important front suspension is. I’m really thinking about selling that converted truck and buying something like we are talking about. It’s topics like this that helps us newbies. The problem with this truck is verified mileage. Having 200,000 miles is a lot different than 1.2 million. Thanks guys for response 

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On an old truck like that ??  miles are probably correct.  That truck wasn't made to go millions of miles. Just not the nature of a construction truck. Hours mean more to one of those. Above and beyond all ??? if it was taken care of is what really matters. Those trucks like in that add were a very good truck for what they were made for, and that one likely still has some life left in it. I didn't see anything confirming that one is even a dump truck ??

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good luck Ricky...  You can't go wrong with the RD 690S...  It will be an adjustment as far as driving it, but that is one tough truck.  I have driven many of them and the repairs were usually thing's like camel back box rubbers and regular wear items, A clutch here and there, and sometimes re-seal or replace a carrier, Mabey a set of torque arms, but as hard as these trucks can work,  no biggie. The E-tech is a good engine with a very simple computer system compared to todays truck's, and can be repaired by a good mechanic. there are some specific tools to do engine work, but they are readily available. I have bought many of them. (I can point you to the tool vendors in the future)...  Then if programming is needed, you can take it to a dealer if you can find one that know's how to use Mack software.  I set up one of my customers with a laptop/ Vocomm box/ and P.T.T....( around $2500.00+) and I can do almost everything with it, to their older Mack's... jojo

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I own and run a 1994 RD690S dump truck with an EM7-250 and a T2070 7 speed and can share my experience: Mine is 50 horsepower less than the one you are looking at. These trucks are not race cars and were never intended to be. The are slow, deliberate and reliable. I run mine doing steel body hourly dirt work so I'm not in a hurry to get anywhere....ever. The second you try to rush the truck, get in a hurry, or think you can pass someone else you will be disappointed and/or frustrated. So many guys I run into say the despise the "puny" 12.0L Mack engine and/or the Maxitorque transmission.    The seven speed is an excellent dump truck / vocational transmission in my opinion. It is essentially a 5 speed (has 5 holes) with a deep reduction button and holes 1 and 2 are lolo and low respectively when deep reduction is engaged. I drive mine like a 5 speed 85% of the time. If I'm starting out on a hill or off road I will use lolo or low depending on the situation. Lolo is the perfect gear for  idling in front of a milling machine. Same with lo reverse. You can idle backwards under just about any load and have excellent backing control. Mine has 6.06:1 rears so its only good for about 62mph on the highway. Every EM7 with a T2070 I have ever seen has crazy low gears in the rear (anywhere from 5:32 to 7 something). This is how so few gears are achieved in conjunction with an engine that will pull down to 1000 rpm. Once you realize what it is and what it isn't you will be fine. Just don't expect it to be a 550 Cat with 3.90 rears and an 18 speed fuller. The other thing too is the engine / transmission are extremely reliable and use very little fuel compared to other contemporary engines. Very inexpensive to operate in comparison. 

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So many guys jump into one expecting it be just like a Eaton Fuller 8LL and promptly wind up jamming and grinding gears then get all jacked off and trash talk them. An 8LL has about 400-450 rpm drops between gears. a 2070 has something like 650-700 rpm drops between gears. You essentially have to wind each gear out to the governor and shift. And like Jojo says take a long pause (light your cigarette or take a bite from your sandwich) before slipping it into the next higher gear (usually around 1050 or 1100 rpm) right where peak torque is on these engines. Down shifting is the other downfall of people who don't understand them. Pull the engine down to around 1100 rpm, double clutch to neutral, then rev the engine up to the governor and push the shifter into the next lower gear. Most newbies just "blip" the throttle like you would shifting a Fuller but its not enough on these Maxitorques. The space between the gears is about 300 rpm more than a Fuller. 

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4 hours ago, Ricky Beals said:

This is just a post for information. Saw an ad for a low miles 2000 rd690s with a seven speed. What little information I can find, not many people like the seven speed for a dump truck. Where these trucks mostly day cab trucks that were converted to dump trucks. Shows double frame,  em7 300 horsepower.  looks like a nice set up all except the seven speed. Just gaining knowledge so appreciate the information 

Looking at the dealers website listing and photographs that looks to be about the most robust, reliable, and efficient dump truck you could probably find. Certainly not the most glamorous or comfortable out there but definitely an absolute workhorse money maker as long as the major components check out OK. I would want to see more pictures of the double frame rails and chassis but from the pics it certainly looks like a good clean southern truck with little to no corrosion. In person I would obviously want to check the engine for blow by and/or overheating head gasket issues. Check the transmission for any whining / bearing noise. Also, another thing to look for on these trucks is if the rear trunnion is in good condition or needs rebushed. A quick and dirty way is to raise the bed about half way so you can see the tandems out the back window and drive in reverse about 5-10mph. If the tandems track straight they are "good". If they walk around side to side while backing they need rebushed. Not the end of the world but something to consider when negotiating a price......speaking of which I'm curious as to what the price for this truck is. 

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1 hour ago, Mark T said:

On an old truck like that ??  miles are probably correct.  That truck wasn't made to go millions of miles. Just not the nature of a construction truck. Hours mean more to one of those. Above and beyond all ??? if it was taken care of is what really matters. Those trucks like in that add were a very good truck for what they were made for, and that one likely still has some life left in it. I didn't see anything confirming that one is even a dump truck ??

Sorry Mark T I don’t understand how to copy the ad but it’s a dump truck. Or it has a dump truck bed on it.67D17C89-F423-4121-B866-7DDE0E2BDE4F.jpeg.58912634b8d2c4b17efa0d1376e6a515.jpegDF3C0F8A-276D-44C3-B1E3-3203D26E4820.jpeg.5fac55f7288896eb64fc5926c0fb853d.jpeg

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1 hour ago, 67RModel said:

Looking at the dealers website listing and photographs that looks to be about the most robust, reliable, and efficient dump truck you could probably find. Certainly not the most glamorous or comfortable out there but definitely an absolute workhorse money maker as long as the major components check out OK. I would want to see more pictures of the double frame rails and chassis but from the pics it certainly looks like a good clean southern truck with little to no corrosion. In person I would obviously want to check the engine for blow by and/or overheating head gasket issues. Check the transmission for any whining / bearing noise. Also, another thing to look for on these trucks is if the rear trunnion is in good condition or needs rebushed. A quick and dirty way is to raise the bed about half way so you can see the tandems out the back window and drive in reverse about 5-10mph. If the tandems track straight they are "good". If they walk around side to side while backing they need rebushed. Not the end of the world but something to consider when negotiating a price......speaking of which I'm curious as to what the price for this truck is. 

Thank you for your very detailed response. I really appreciate your time. He wants 38,000.00. I figure you could offer him 35,000 cash and get it. The door rails are a good way to check for wear. Could you discuss how you look for overheating with head gasket please.

 

also I’m not familiar with that style dump bed. We mostly haul gravel and small stone where I’m from. How would that bed work with those items.

Hiw much weight can you haul in that dump bed? Rough guess

Edited by Ricky Beals
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Like onyx said , at least one wheel seal is gone, cylinder on the bed needs repacking soon but will last the way it is, just gotta check hydraulic fluid so you don't burn up your pump..also missing the dummy light in the dash above the tach and speedo...can't remember if it's the parking light or the lightning bolt.lol...nice truck other wise..also they installed a new floor on top of the old one on the bed..you can tell because the bed is wavy looking at it from the bottom but looks new looking at it from the inside..it's not bad just makes the truck a bit heavier.

 

Red

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Man you guys don’t miss much. I definitely understand you guys have learned by experience. Nice to see how you guys see things I don’t, but when you guys point them out I see them

 

onyx610 thanks for the add

Edited by Ricky Beals
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