1989 International 1954. Change transmission or rear end?

[fourwheelinj1]

We just bought a 89 International 1954 16' flatbed dump 32k GVWR with 210hp 466, 5 speed manual, air brakes, and a 4.44 rear end. The truck was owned by a local small town that hardly ever used it. It only has 80k miles on it. The truck is being delivered tomorrow so I haven't had time to really test it out loaded yet but I am concerned about the 5 speed and a 4.44 rear end. We will use the truck on our farm which means heavy loads and off road use. Our current truck has a 2 speed rear that we use a lot. If the gearing isn't low enough and I need to change something to lower the gearing what would be better swap the trans or the rear end? If I swap the trans I could swap in a spicer 6+1 which i think would give me decent low and top end but that means a new pto and driveshaft length. For the rear end can I just swap in a 2 speed rear and add the needed electrical? If so does that means just swapping the third member or the whole axle assembly? Last question, on trucks like this with different GVWR are the axles actually different or just the springs?

Sorry for all the questions. I do a decent amount of work on older light duty trucks, jeeps, small engines etc, but I am just starting to learn the medium and Heavy duty stuff.

 

[tpitt]

I would try and find a 2sp. rear end. I have a 2001 with the 6+1 and it's fine going forward, but reverse is way too fast. It has 3.73 gears though, but the tires are 225/70/19.5.

 

[Shimmy1]

If you're worried about not having enough low gears, a two speed isn't going to help you much. Two speed rear ends don't stand up to hard use in the low gears, in my experience. What you need is a 13 sp direct, or an 8LL. My dad has a truck that had a Fuller RT613. Awesome trans for crawling around in soft ground. We repowered the truck, and needed a trans with OD, so we put in a RTO9513. That would also be a good candidate for you.

 

[RZucker]

If you're worried about not having enough low gears, a two speed isn't going to help you much. Two speed rear ends don't stand up to hard use in the low gears, in my experience. What you need is a 13 sp direct, or an 8LL. My dad has a truck that had a Fuller RT613. Awesome trans for crawling around in soft ground. We repowered the truck, and needed a trans with OD, so we put in a RTO9513. That would also be a good candidate for you.

JMO, I think a 2 spd rear with a 4.44 high would do the job for a farm type truck. That rear end would have a 5.38 low range? Now... if it was a tandem dump, yes I would do a trans swap.

 

[Delmer]

That 5 speed is probably a granny low and a direct top gear. I wouldn't touch a thing for farm use.

 

[Shimmy1]

That 5 speed is probably a granny low and a direct top gear. I wouldn't touch a thing for farm use.

That's what I wanted to say, but those 5 sp Spicers have a pretty strong 1st gear. Then again, it might not be a Spicer, in which case I don't have any experience other than what I've stated. I do believe if fourwheelin swaps in a two speed rear because he's having trouble getting around, his problems have only just begun, IMHO.

 

[fourwheelinj1]

Like I said I haven't tried it out yet. Hopefully it fine as is. If not I will keep my options open.

I am also planning on replacing all the fluids/filter, hoses. belts before I start using it much. What fluids do you guys recommend? I don't think there is a manual for the truck. I am planning on Rotella 15w-40 for the engine oil. Any specific coolant to use? Which grade oil for the trans and rear diff?

 

[Delmer]

Yes on the engine oil. Extended LIfe Coolant, ELC (Peak Final Charge or a name brand) or SCA precharged heavy duty coolant (Fleetcharge from peak) depending on which style you want to maintain. Drain the coolant hot after it's been used for a while, if it's clean when you drain it, no sediment in the bottom of the clean bucket, then there's no point in flushing unless you're going to ELC. Then flush it with distilled water, or rain water first.

 

[fourwheelinj1]

Somebody please educate me on the proper way to handle SCA in a truck like this. Lets say I change/flush the coolant and use FleetCharge which is SCA precharged. Then there is a coolant filter to change correct? Does the filter have anything to do with SCA? How often do I need to check the SCA levels and what should they be? What is the best SCA additive to use for the 466?

Also any fluid recommendations on the trans and rear end?

 

[Shimmy1]

If it has a coolant filter, and you decide to drain/flush/replace with a SCA pre-charged coolant, you need to replace the coolant filter with a 1 unit filter. A normal 4 unit maintenance filter might get SCA levels too high. If a 4 unit filter is all you can get, don't worry about changing the filter until an SCA level check requires you to bring the level up. If the truck doesn't get many miles, you might not need to add SCA for quite a while. As for your fluid question, I would put 75-90 synthetic in the diff, and whatever the transmission requires. We always ran 80-90 in our 5 sp Spicer, but if it's something else, it could require 50 wt. engine oil.