mackncheese

I would say a half gallon every 3-400 miles. What is a bottle test? Thanks

99 rd 690s seems to be losing coolant. I don't think it is a leak. Although a while ago she blew coolant out the overflow. Is there a test to determine if the head gasket has failed. I am not sure a pressure test will show it as the loss is gradual. Also the other day, i had an intermittent engine miss. It was the first day of really hot weather. I don't think the 2 are related but thought I would mention it. Thanks for your time.

I installed a jake on my 1999 E7 ETECH 400 and it does not brake very well. I spent about 3000 buying it and getting it installed and I wouldn't spend that money again. One thing that did help was when I changed my oil the last time I added a gallon of Lucas. That has definitely helped but it is not near as effective as the jake on my truck with a 400 big cam cummins. Somebody on this forum recommended the Lucas and it works. Do a search on jakes on this forum and you will see that others have not had much success with them on E7s, something to do with oil pressure(?????)

Sivart, is your road ranger a new, reman, or used? Are you doing the swap yourself? What torque rating is your road ranger? I was thinking of 4.42s in the rear, what road speed are you expecting with the 4.64s? Thanks

I am in Virginia, can anyone of you recommend a good dealer or independent to do the work for me that is in Virginia?

Thanks all of you. Yes, it basically is a 5 speed with 2 compound lows. I have never seen the EGT over 1000. My boost is as high as 28lbs. The truck was originally a 300hp E7 VMAC lll that I had a dealer modify to a 400 hp. I assume this swap has been done before.

The space or step between all gears is too much. I pull a 20 ton tag with a 160 trackhoe in a hilly region and it is really sluggish. even on a pretty flat road in 5th you can watch the pyro temp rise. I think fuel mileage will improve but I realize there will be no return on this "investment". I just don't enjoy driving a truck that won't go. I have a 79 Ford LTL with a 400 big cam and a 13 speed and that truck really pulls. The Ford is old and rough so the Mack is the main truck.

Got a 7 sp 2070B in a 1999 RD 690 S with a 400hp E7. I love the truck but hate the transmission. Would like a 13 or 18 speed. The truck is a low mileage and in very nice shape and I got it pretty cheap. I know I will have to change the rear gears as mine are 5:32. I realize all of this will be expensive but I have been looking at trading the truck in and can't find a truck in similar shape as mine for close to the money. My question is how complicated is this swap. A parts guy at a Mack dealer acts like I am crazy for even considering this. Thanks for your time.

I have a 99 RD 690S and the truck gets stuck all the time in conditions that I don't think are all that tough. I have a power divider that is air actuated and has a blue light. Is there a Mack axle locking system that would go in my Mack rear end housing? I want something that I could flip a button in the cab and have both axles turn like a spool or something close to that. I am ready to spend some money to get this done as I frequently work alone and getting stuck is very frustrating when there is no dozer nearby to pull me out. The rears are 44s. Thanks for your help.

I have an update. I have a close friend who he and I use each others equipment at times instead of having to rent stuff. Well he used the truck and put 20 gallons of gas in it. I ran it for about 2 hours and put about 15 gallons of diesel in the driver's side tank. Then drove it about an hour more to the Mack shop. My question to you guys is what kind of damage did I do. The Mack shop said it got worse at their shop and started cracking and popping. Then they discovered the problem. What do you guys think?

Will the carriers fit in my 1999 RD 690 S? I have 44,000lb rears with 5:32 gears with a 7 speed. I am looking to switch to a 13sp or 18 sp and the 5:32 wiil be too low.

I have a 1999 RD 690 S with a 400hp E7 (mack dealer modified) with a 7 sp trans. It is a ETECH VMAC lll. The problem I had was I started sensing low power when pulling a 35000lb loader on a tag trailer, the boost is off about 4-5 lbs and sometimes I can hear a miss in the exhaust. Also I think the pyro temp is up but I can't say for sure. It is hard to see the exhaust but I did catch some abnormal blue/white smoke on an upshift. You can't always hear the miss. What do you guys think it is? The Mack dealer is an hour away and I don't want to take it there and have them not be able to "see" the problem. In other words, because of the 7sp the truck can be sluggish and don't know if they will road test is and say nothing is wrong. What do you guys think is wrong and should a dealer be able to plug in and see the problem? Thanks for your time. The VIN is 1m2p264c5xm029458

Thank you all for the info. I will dig into it over the weekend unless the problem shows up before then. I will let the forum know what I find. If I find the VECU proper with no corrosion should I buy a power relay and keep it on the truck?

I have a new to me 1999 RD690S with an E7 etech vmac lll. the other day it spun over a bunch and would not start. It had been running an hour earlier. I was ready to call my wife for a ride and tried it one more time and it started and has run fine for a day now. any idea what to check? I don't want it to bite me one day. Is there a fuel pump solenoid? If so where is it? Any other ideas. thanks for your help.

thanks for all your responses. The Mack had the uprate done at the local mack dealer. It was not dynoed after the update but I could feel a difference. the dealer checked fuel and boost pressure and both were reportedly where they should be. the 400 big cam in the Ford has been turned up some but I don't know how much. You seem to think it is a horsepower thing where as I feel like if I could keep the Mack in its sweet spot it would pull much better. On the highway the ford can't stay with the Mack. It is the hills and getting up to speed where the ford is so much better. First thru third is strong but 4th and 5th are weak. Thanks again for all of you alls input

I have a new to me mack dump truck and I really don't like the 7 speed and I want to make a change and I have read the entire engine and transmission forum twice and have a better understanding but I am still having trouble with what is the right choice for me. I need to maintain the off road ability and I live in a hilly area and tow a 20 ton tag with a 20 ton track hoe. If I can go 65 on the highway and am not redlining the engine that is good enough for me. Here is what i have: 1999 RD 690s with a 400hp VMAC lll E7 ETECH. (uprated from 300hp at the Mack dealer) 7speed T2070B with a 44000 rears with a final drive ratio of 5.32 Tires are 11R22.5 VIN is 1M2P264C5XM029458 Right now I can go 75 on the hiway. I don't need to go that fast. We were hauling dirt the other day and my Ford LTL 9000 with a 400 big cam and a 13 speed (I think) would eat the mack up. there was a hill on the run and Mack no matter what you did would crest that hill at no more than 35 mph. the Ford would crest that hill at 55 all day long. the Mack's bed was larger and it was hauling about a 2 tons more dirt than the ford, but it would not have made any difference. First thru 3 is strong but once you hit 4th and 5th it dies and slowly builds rpms up to its power band. Very annoying with a line of traffic behind you. What transmission do you all recommend based on the info I have give you? What we will give similar performance as the Ford and what trans will swap out with the least hassle. Can I have the 7 speed modified to a 9? Thanks in advance for your help.

What engine and transmission due you have in those trucks? I have always liked those DMs especially with the floaters on the front. Do they ride rough? I heard converted concrete trucks rode rough when empty.

Joe thanks for the reply. When I first bought the truck I had to drive it 2 hours to the Mack dealer. the truck was not modified at this point and was 300 hp and it/I was shifting the same way and seemed to fall into gear at 800 or so. In other words the shifting behavior didn't change (at least that I can notice) when we uprated it to 400 hp.

Been wanting a Mack Dump for a long time and finally bought a 1999 RD 690s. It has a E7 Etech that originally was 300hp but I had the Mack dealer uprate the engine to 400hp. The final drive gear is 5.32. I have only driven the truck twice (empty) but I can tell the difference in the increased horsepower. My only potential issue is the 7 speed transmission(2070). I am not shifting good yet but the gears seem to fall in at about 8-900 RPM then the rpms are slow to climb. Its making me wonder if when loaded it will always lug till it gets up to 1200 or so? I live in a somewhat mountainous area and have a 20 ton tag and will tow a 160 Trackhoe at times and I will be disappointed if it doesn't pull strong at the lower rpms. I have a LTL 9000 Ford with a 400 big cam with a 13 speed and it pulls really well. I just hope the Mack won't disappoint me. Do you guys think that the 7sp was a mistake for my application.

I just bought a 1999 RD690S with an EM7 300 ETECH. I gave the VIN number to the dealer and he sent it off to the factory and they told him that to get 400 hp I would have to change the injectors and the turbo and update the computer. To put in 6 Mack Reman Injectors, a mack reman turbo, reprogram the computer, and resticker the engine would be 3650. It is in the shop getting it done now. The service manager said that many have uprated the EM7 ETECH to 400 and it did not overstress the engine. I think mine is a VMAC lll.