Free 7 Day Trial RV GPS App RV Trip Planner Campground Reviews RV Maintenance Free 7 Day Trial ×

Thread Tools Display Modes
Old 05-27-2021, 07:54 PM   #1
New Member
Join Date: Feb 2021
Posts: 3
Bulletproofing 2002 Fs65

Hello, I recently bought a 2002 Freightliner FS65 Thomas built. 5.9 ISB Allison 2000. I just drove it 900 miles in 2 days and it ran perfect. I want to bulletproof the motor and trans. Preventive maintenance or upgrades. My gvw is 29 but I'm under 20k loaded. Taking it easy. I just want to make the most reliable motor ever more reliable. I come from 25 years of driving a Ford 7.3 diesel van or truck. No Cummins knowledge.

I just bought Fleetgard Lube and Fuel filter. Gonna switch to Rotella T6 5 40. I want to get the trans fluid, coolant, differential taken care of next. Speedco wanted 349. Oil filter, fuel filter, 3 gallons of T6. Less than 100.

I am looking to bulletproof anything on the chassis. Bus was extremely well maintained by Midwest in Van Buren Ark. Already has a rebuilt trans and motor. Runs like a top. I just like to overengineer stuff. The inside is already done so all my money is going in the chassis.

BabadDo'Ag is offline   Reply With Quote
Old 05-27-2021, 08:07 PM   #2
Bus Nut
Rwnielsen's Avatar
Join Date: Jun 2020
Location: Long Beach, CA
Posts: 454
Year: 1998
Coachwork: Blue Bird
Chassis: TC1000, 40' MPV
Engine: 5.9 Cummins/B300 trans
Rated Cap: U/K
Good for you. Most people seem to care more about the paint and such. I'm doing the same with mine, it's a comforting feeling feeling knowing what's going on mechanically. Mines a couple years older ('9 and I'm psyching up for the "killer dowel pin" remedy. At least I'll get to change the belt while I'm in there.
FWIW There's a handwritten note on mine that says 17 qts. Mine is a 12v though.
Rwnielsen is offline   Reply With Quote
Old 06-12-2021, 11:12 PM   #3
Bus Nut
Simplicity's Avatar
Join Date: Aug 2019
Location: Auburn, WA
Posts: 682
Year: 2000
Coachwork: IC / Amtran
Chassis: 3000 / 33' Flat Nose
Engine: IC T444E / Allison MT643
Rated Cap: 72 Kids / 48 Adults
Based on the OPs 7.3L history, none of this is new to him probably, but I thought I'd share what I'm doing to get my bus in shape and keep it running well.

In general, what I like to do is do a solid job of cleaning all the built up crud, oil, etc. off so I can see the zerk fittings, watch for where anything might be leaking, etc.

Then I like to inspect and make sure things are secured, zip tied, etc.

I have taken things one step at a time, for the most part, and repaired or replaced as needed. I didn't start out this way, but I've learned.

Per fluids and filters, the general gist I get from what I've read on here is a decent fluid + a decent filter changed more frequently than not will provide the best overall protecting your drive train.

I used the following:
Baldwin filters
Shell Rotella 15w-40
Valvoline full synthetic ATF (they claim it's transynd equivalent, but don't want to pay to have it certified)

I initially used Power Service fuel additive, but after watching a great YouTube comparison of like products, I am switching to HotShot. A friend switched from Power Service to HotShot after I told him about the video, and said he was amazed how his Cummins 5.9 24v ran with the HotShot.

Oh, one problem he's had with his Cummins is if any air gets in the fuel line, it locks up his injector pump and no start. The first time he did this, he didn't pay attention to it and it appears cavitation ate the pump. He has a new pump, but it happened again. He suspects his fuel gauge is off a bit and he runs the fuel level too low. He's now going to keep it at a 1/4 tank or more to avoid wrecking another injector pump.

I've added a Griffin cooler, (the larger one), for my tranny, but have yet to hook up the new hoses. s2Mikon turned me onto his setup and I flagrantly copied it. 1.75" tube and 1600+cfm fan with a 200F on / 185F off thermo switch.

I'm just about to dig into my cooling system. My engine uses good ol' green antifreeze. I'll use pre-charged with a DCA pellet coolant screw on filter (T444E and cavitation prevention).

I've got a viscous clutch fan (I think), that appears to be in good condition, but honestly, I'm not sure. With a hard pull, it spins exactly 5 times, so it seems okay. But, the whole fan activation system is suspect. I don't hear the fan "roar" that others speak of and my coolant temp is always right about 210F, which is well within operating range...but??

So, I'm pulling the radiator, all hoses, thermostat (depending on how things look....maybe the water pump) and upon recommendation, the accessory pulleys. I'll test them and see.

New hoses, thermostat, power wash the radiator and charge cooler, determine what kind of internal treatment they may need.

I also am wondering what kind of shape my bi-metal thermo coil is in. I don't know if it's filthy, broken, adjusted properly (if it can be adjusted), etc..

I've read up on the Horton electromagnetic fans, but I'm not sure I need to go there.

The main issue I have with my coolant system is my top radiator hose always collapses during cool down. All I have to do is release the vacuum via the coolant tank cap, but I need to determine why it's not releasing the vacuum automatically. A new Motorcraft 10psi cap didn't help.

I figure the more I run it on the cooler side of the operating ranges, keep the fluids viscous, the filters clean and levels good....I'm doing the best I can.
Simplicity is offline   Reply With Quote
Old 06-13-2021, 05:55 AM   #4
Bus Geek
Join Date: May 2009
Location: Columbus Ohio
Posts: 15,214
Year: 1991
Coachwork: Carpenter
Chassis: International 3800
Engine: DTA360 / MT643
Rated Cap: 7 Row Handicap
the upper hose may just be worn and collapses. . you could put a spring in it but its not necessary..

in your car you have a coolant recovery tank.. when the pressure in the system gets too high (over the cap rating) (coolant and air expand as they heat up and create pressure).. then the system vents.. if its full it vents coolant int othe recovery tank.. when the engine cools down the same expansion that took place during warmup needs to reverse.. a vacuum is created.. in a car it will suck coolant back into the system from the recovery bottle..

in the busses there is no bottle (but you can make one.. (diet coke 2 litre to the rescue) so when the system expands it just blows the excess coolant on the ground or if you fill it too full. I made a recovery bottle for my DT360 and will be doing so on my T444E.. the results have been fantastic.. the issue with busses is dur to the hugely increased size of the heater loops compared to a normal truck you have much greater expansion and contraction if your heat valves happen to be open.. (some people dont close them in summer).. while the heater valves can be a great source of extra coolant capacity for a less than stellar system it can also mean you blow more coolant out than you want to..

210 isnt a bad temp, i have my fan set cooler but 210 is quite OK for a 444E.. my fan is at 204 on and 198 off and im running a 180 (instead of standard 192) thermostat.

the horton clutch is the best thing I ever did but my bus liked to get warm, since the horton and allison 2000 update i dont erven think about temperature anymore.. and thats with my horsepower cranked up. on really hot days hauling ass with the AC blasting my fan may run near constantly but the horton clutch is 100% duty cycle rated.. I attribute some of the constant fan to the low RPMs in 6th gear.. my fan run times are less if i drop the trans to 5th as the engine spins a little faster..

if your bus runs cool on the viscous clutch theres no reason to change it.. I did it because I always ran hot. I have a viscous clutch in my DT360 and it works fantastic.. that bus never even sees 200 even in 100 degree heat so I wont touch that one.

cadillackid is offline   Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

» Featured Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 07:56 PM.

Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2021, vBulletin Solutions, Inc.