Newbie w/ '89 D250 2 wd questions

[btoscano]

Hello,



Checking out a diesel Mercedes today, the owner also had a 1989 Dodge 250 2wd for sale w/ ~109Kmi. It was the first time in one of these for me. I was surprised at the smooth steering wheel and overall comfort as I drove down some Kentucky highways and interstates. From a stop, the truck accelerated faster than I expected to 50 MPH and even to 70 MPH was pretty quick. But it did not go past 75-80 MPH and to hold ~75 I up a light grade I had the pedal all the way down. The transmission seemed to shift smoothly, oil pressure was halfway between the middle and the right side of the guage. Overall I was impressed, I thought it would ride much worse. But I don't understand the top end speed. The owner used it to drive his farm tractor from his barn to a few places around town and offerred the idea that it was speed governed. For him it didn' matter as he didn't drive it much. There was no noticable smoke.



Does anyone have any ideas why the truck would no pull to 80+ MPH? Otherwise it seemed in nice shape.



Thanks,

Brian Toscano

1987 300D 279Kmi

wishing to be a Dodge Cummins owner

 

[Philip]

This year model truck did not have a overdrive trans in it. It has a 727 3 speed auto.





With 80 being the top end. Sounds like it has 3:54 gears in it. The 3:07's would have toped out around 90 mph.



The top speed was a problem on the non over drive equiped trucks. They run good but the engine was almost on the governers to hold a good road speed.



Welcome to the TDR

 

[Wayno]

I would guess the truck had an auto in it and if so it is a three speed with no Over Drive and that is about all it will run in top speed . If you want it to go faster you will have to put a overdrive unit behind the three speed transmission(like a Gear Vendor OD unit) or swap out the transmission to a 91 1/2 through 93 transmission that has the Over Drive and that might be a little to much work .

 

[rowland]

max speed

My '89 would max out a 78 mph WITH 3. 07 gears. It should be governed at about 2500 rpm. This can be raised a little using the governer screw but your cruising rpms will be high. I found that it would really kill my mileage to do over 65. Great as a work truck but not fun at freeway speeds.



Of course a transmission swap such as I did can change all that, but it is somewhat of an investment. Of course having a two wheel drive does make things easier.





Isaac

 

[btoscano]

Thanks for the replies! I should have said production date was late 1989, so its a 1990 model - does that change my options? Isaac pointed out 78 MPH and I'd say that's my experience. Is the 3. 07 Okay, or should I look for one with a 3. 54?



How much would the conversion for the transmission &/or gears cost approximately? What aboutthe reliability of each?



If I'm asking what's already been asked and answered many times please point me in the right direction.



Thanks,

Brian

 

[rowland]

It would be worth checking which gear ratios you have. The differential cover should have a tag on one of the bolts that will tell you what it is. With the low end of these engines the 3. 07s will work fine for most things. However if you plan on doing nothing but towing/hauling with it then I would guess that the 3. 54s will help you out.



Swapping out the three speed 727 for the four speed A518 is a relatively simple matter in a 2wd. Once you drop the original the 518 will bolt straight up. You will then need to have the rear driveshaft shortened and the OD will need hooked up via a manually operated switched power source.



The hard part will be finding a donor from a 92-93' cummins. This is also the expensive part.





Isaac

 

[ptrodock]

I had a 91 with the 727 transmission and 3. 54 gear. I topped out around 75 mph. It is a bit of a bummer, but I put nearly 300,000 miles on it and never had a single transmission problem, the thing was bullet proof.





Good Luck, it sounds like a good truck!

 

[btoscano]

I'll stay with the 727 for now.



I have a few more questions (again, if this information is elsewhere, please let me know).



Coolant temp guage - what's the "normal" reading for driving w/out any load? Loaded?



Oil pressure - what should it read? There were no numbers on the guage, but when I drove it, it was halfway between middle and the right side iirc.



Thanks,

Brian

 

[LVarhaul]

I have a 1989 W350. It is equip. with a dump. It seems to top out at 40 45 mph. I am not sure, but I believe I have 410 gears in the rear. I don't have a tag on the rear, so is there a way to tell what gears I have?

Any help would be great.

 

[sdstriper]

The whole throttle system, linkage, ball ends, cable etc. is likely out of adjustment or worn, stretched etc. My 89' was the same way when I bought it, it had much higher mileage though. The pedal effort was ridiculous, drove it 750 miles home and had a noodle leg because of it. I think that contributed to wear etc. The top speed was similar. Was. New throttle cable, ball ends, bell crank bushings, throttle pedal was shot, adjusted all and in fine tune it will bury the speedo (85mph) and climbing. I have the VE turned up but all the worn parts gained a large amount of travel and eased the effort. Night and day difference. The 727 and 3. 07 have nothing to do with it. If you dial in the throttle system and tweak the pump a bit, you'll be running freeway speeds and have passing capability if you chose.

 

[LVarhaul]

I don't want to show how stupid I am, but is somewhere I can see a diagram or explanation on how to go about replacing or repairing this problem . I am not too mechanically inclined, but I should be able to do this. Any help would be great.

 

[Pleines]

Where and how much does this guy want for the 89'?

 

[Forrest Nearing]

you'd probably have to go back in time about 5yrs to find out

 

[Pleines]

Hm, maybe I should look more...