93 F350 7.3L Tranny Question

[rorabeck]

Hi guys, I am new to the ford diesel world but not new the diesel in general!

I just purchased a used U-Haul Truck, 14ft which is a F350 powered by 7.3L diesel. It has 275K on it matted to a automatic tranny. When I took delievery the guy said the tranny will need to be adjusted because the engin speed should be slower when operating on the hightway. I used the gear shift and when threw 1, then 2, then Drive and it shifted each time. My thoughts are this guy is use to the newer tanny's. The RPM's are 2500 at 80KM/h or 50 mph and around 3100 at 100km/h or 60 mph. Should I be aware of anything? I do not see a tow butten or anything that indicates a OD.

Thanks Dave

[pipelayerjdh]

The OD button should be in the center of the gear shift lever, if it has one. I don't think you could get a C6 in '93, but I'm not sure. What rear end ratio is in it? 3100 RPM is high to be running extended periods.

[powerstrokes only]

I think U-Haul was able to get the C-6 for a while, I have seen them advertised with the C-6, RPM's sure point toward a C-6 too. I did not Know U-haul used the 7.3 past '91 though.

[rorabeck]

I am not sure what the rear end ratio's are, but it does seem to be high rev's.

[powerstrokes only]

I am sure it is a 4:10 rear end, we had an '89 7.3 with the C-6 and a 4:10 and a Gear Vendors overdrive unit. Without the over drive it was super slow!

[rorabeck]

Originally Posted by powerstrokes only

I am sure it is a 4:10 rear end, we had an '89 7.3 with the C-6 and a 4:10 and a Gear Vendors overdrive unit. Without the over drive it was super slow!

How does the Gear Vendors overdrive unit work? So it is possible that there is a overdrive on this unit? What would I look for so see if it does?

[rorabeck]

Ok so the OD would look like this on the tail of the tranny?

Gear Vendor Over\Underdrive overdrive two speed NICE!!! - (eBay.ca item 150209897881 end time 31-Jan-08 20:44:52 EST)

[viper5]

I have a 91 F-350 old U-haul truck 7.3 w/C-6 trans 4:10 gears and my rpm's are the same as you have with yours. Sounds like you have a C-6 in the truck

[rorabeck]

Originally Posted by viper5

I have a 91 F-350 old U-haul truck 7.3 w/C-6 trans 4:10 gears and my rpm's are the same as you have with yours. Sounds like you have a C-6 in the truck

Thanks for the update, What kind of millage do you get in yours? The guy I got from was really concerned about adjusting the linkage when its in the shop and said the truck wouldn't last long if it was not done since it revs so high. I personally didn't think there would be a OD, and thought it would make sense that the unit would max out in speed at 105km/k or around 64mph so the renters would be going all crazy on the road. My other though is diesels are governed so low that in the even you were running it wide open there shouldn't be an issue except for millage.

I have a friend a coca cola and their international are set for about the same speed with a 5 speed manual and the only way they will exceed if they ride the clutch, but the engine speed is low around 2800 rpm (much newer of course)

Is there any recommendations on service or things to watch out for since it was a daily rental. I got mine from U haul, and its getting safetied this week. On delivery the only two things I noticed was high revs and the steering needs to be adjusted, tire rod end something to that effect. No smoke except on start up, which I can live with since most do when its below freezing. For an investment of 3K it seemed to be a great deal

[viper5]

Dave, I get around 12-14 mpg with mine, top speed is 70 @ 3,500 rpm, U-Haul's main purpose for these trucks was local moves so thay kinda rev out on the highway, I take it in the interstate and as long as I keep it around 68 I have never had a problem with the rpm's being high. As long as there is a load on the engine it wont hurt it to run @ 3,000 rpm.

I have a spin on transmission filter on mine (HP-1) that U-Haul uses to make transmission service easier, if you have one I suggest changing it. Other than that all maintance is the same as any other diesel