oilburner

An RTX 9 and an eaton 13spd both have the same top gear ratio, one has .73 in 9th the other has .73 in 13th. I know it can be confusing if you are new to it but it comes with time, the easiest way to get more road speed is taller tires, with an 11R24.5 tire, eaton OD trans(.73OD) and a Mack 4.42 rear you get about 74mph at 1800. I try not to turn my truck that high for extended periods I like the 15 to 1600 rpm range its a lot easier on the engine, I think with your current road speed the best gear ratio for you to try would be 3.86 there are carriers out there with this ratio(I am actually wanting a set now I have 4.64 gears) I know that 4.17 is a good ratio for taller tires like 11r24.5's but sounds like you are running 22.5's with the rpm you are turning. I would ask are you running spoke wheels or budd/disc wheels? if you are running budd wheels a wheel tire swap would be a lot cheaper than a gear swap if you can get a tire shop or other truck owner to give you some money for yours, a set of CRD92/93 chunks with 3.86 gears will be $1500 to $4000 depending on condition. I hope that info helped I have been there before and like I said I want to make a swap now Im just waiting on winter (and more money).

I do like the 4.17 gears which is what the truck i run now has but it has a 13 speed maxitouqe trans and it runs 70 at about 1700, but he can put a 13 speed box on his trans and make it a double overdrive and lower his rpms at crusie and split the last four for more proformance, i ran a truck with this trans and 4.64 that pulled quit well.

The trans is a RTXF14609 B . the guy on fuller said that i wouldnt be able to increase topspeed at a lower rpm though with a 13 speed which doesnt really make sense to me. so i have to change the rear end and the trans just to get more useable power and fuel economy? is this the only option? how much does this all cost?

Come to thank of it that is basicly the same trans as a 8LL without the deep reduction, and yes i do belive you can actually but a 13 speed rear box on that trans and make it a double over because you allready have a overdrive in the main, all you would be doing is addin the overdrive section from a 13 speed on you trans. That is what you split the gears with anyway

Nevermind, i think i understand it now. I cant get more out of my top gear because its maxed out but if i want to split the other gears to drop down the rpm i can. if i max out 7th gear and want to drop the rpms down a lil lower then i can do that but i cant do the same with my final gear because it doesnt have a gear after that to share i guess. im talking about if i had a 13 speed by the way. hope i didnt confuse you all but i think i finally understand all this now lol

I thank you are wanting a trans that will allow you to have more top end. Now i do not know what engine your truck has but with that ratio you could run a 13 double overdrive, which is a 13 speed overdrive that the countershafts have been fliped, which gives you three overdrive postitions, but it also make all thr gear ratios higher in the trans you lo ho is more like frist gear in a 10 speed. My other question is what size rubber are you running on the truck, if you have a low pro or 22.5 you can change to a 11r 24.5 and gain about 5 miles an hour or more. I ran a mack superliner with a 13 double over with 464 ratio, but it had a 400 cat in it and i could run about 70 at 1900 or so and she would top out at about 82 at 2250, now if you are runing a mack engine i have allways liked a 15 speed fuller behind them they also have a good overdrive and give you a deep reduction in the lo lo positon, i hope i have helped you some and the shop book you have will help you also so the 13 double over may be the way to go if you are not loaded heavy all the time.

Ive got the same sort of problem with a 427hp E7. The only difference is that the smoke only lasts a few seconds. Similar cause you think? Check engine light does not come on at any stage. Regards, Skip

I would say we have a very related problem, it only does it bad when you frist start it the frist time of the day, the smoke will last about 15 20 secs. and then it smooths right out and like you said not malfuction light, but even if you cut it off about a hour even if it is still warm it will do it for a few sec. so maybe my problem is the same as yours just a little more advanced.

Most likely the econovance oil control solinoid is worn and slow to advance on start up injection pump rack controls geting worn also not usually a issue wiring going into pump and connections are the biggest issues to deal with. So if its just a start up issue right now and no malfunction lights then good to go welcome to BMT sounds like you have a nice truck how about some pics.

Thanks alot, So i guess it is allright for now but will probely be a problem this winter when the temp. drops don't thank it will crank up to good the way it is. and thanks again the more i drive it the more i like it, broke her in good today pulled well tubeing in some rough place droped the trailer and went and got another load. The only thing is it seems like your are driving a small block chevy, she does good job just got to keep her at peak rpms when you are loaded to get anything out of it but i will say this the thing will pull hard around 1400 or so not like the detroit i am used to that once you do start loseing power it hard to get it to level back out pulling. And i did put some pic. in the garage section.

Name: mack ch 613 (1998)

Date Added: 04 September 2012 - 11:41 AM

Owner: oilburner

Short Description: day cab ch 613

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Hey everyone this is my frist post and i was wordering if my 98 e7 454 has a problem or not. If you start it up frist thing in the morning it runs rough and smokes white for about 30 or 40 secounds and has no throtle respones, but it will run like this for just a bit and then runs fine, untill you cut it off and go back to start it again, when it is warm it only does this for about 20 secounds or so a little less than when it is cold, no is this normaly or a developing problem that will leave me on the side of the road, no other than that it runs fine it had a leak in the primer pump and i thougth it was letting the fuel drine back but replaced it and the truck still does the same thing, this is the frist e 7 i have had so what do you all think?

Hello everone my name is eddie, and i live in south eastern kentucky, The truck i drive is a 1998 ch 613 with a forward front axle, i mostly work in the gas and oil fields here in ky and tn but also help a buddy that logs as well. This is the frist all mack truck i have ever drove, with a 454 e7 engine and a 13 speed maxi touqe trans and 44 mack rears on camel backs with 4.17 rears. I can't wait to see what kind of service this truck gives in the rough working conditions of the oil and gas fields of old kentucky, i will keep you all posted thanks