Engine/Transmission (1994 - 1998) max speed in 3rd gear

[Crowhurst]

What should be the max speed at WOT in 3rd gear with OD locked out in my stock 12 valve? Empty, I can pull about 63 mph, 2600rpm. Towing at 6800 pounds my maximum is 60 mph. This is on level roads, no wind, temperatures in the 70s. Is this normal? I have just changed the fuel filter after picking up some dirty fuel at a small, little used, pump. My next stage is to clean the pre-heater, but I need to know if I have a problem with these figures. I had never previously tried to exceed 60 in third, so I don't know if it's always been the same. The truck pulls fine in OD, and will pull my 6800 pound travel trailer as fast as I ever need to. I have never towed it over 70, but it feels as if it would go a lot faster. Without the trailer, 80 is very smooth, and it will certainly go faster. However, I like to pull at about 65 mph on interstates, so I always have to be in OD. Do these figures indicate a problem? I always spray the TPS with contact cleaner every couple of months, and my knowledge on performance matters runs out about there. Thanks. Nick.

 

[wsmalley]

That sounds about right. Stock springs and fuel are cutting off about that time. Get some new Gov. Springs (I recommend the 4000rpm kit) and you will discover a new meaning to RPM band

 

[Howard Durand]

I agree with wsmalley. Your speed and rpm is about right. That is what I got before the GSK upgrade.



I just installed the 3000 rpm set of governor springs in my 94, as recommended by Piers, and it is undeniably the most dramatic upgrade I have ever done.

It is like I got a new truck for $125. 00.

It no longer lopes at idle and the acceleration is great all the way up to 3000+ rpm in 3rd.



I can't wait to hook up the trailer and head for the hills.

 

[Crowhurst]

Thanks guys, I'm reassured that I don't have a problem, but puzzled at the 2600 rpm stock restriction. The owners manual says don't use OD when towing, so logically, one shouldn't tow at over 62 mph. I'll search for links to explain the procedures for up-rating the governor spring, but I'd be grateful if anyone has any links to explain the advantages and any disadvantages of the change. Thanks again. Nick.

 

[britannic]

Crowhurst: you have an advantage over your cousins over here, in that you can feed your Cummins cleaner and hotter cetane diesel , not to mention you have a bigger gallon too. Europe is definitely more diesel friendly, sigh...

Originally posted by Crowhurst

Thanks guys, I'm reassured that I don't have a problem, but puzzled at the 2600 rpm stock restriction. The owners manual says don't use OD when towing, so logically, one shouldn't tow at over 62 mph. I'll search for links to explain the procedures for up-rating the governor spring, but I'd be grateful if anyone has any links to explain the advantages and any disadvantages of the change. Thanks again. Nick.

 

[Crowhurst]

Britannic, $6 a gallon for diesel in England !!! I use my CTD in the USA, and a diesel Land Rover Discovery (30 mpg) in the UK. However, we have free healthcare in England, so we have to pay for it somehow. I try to travel in the USA, and get sick in England! Nick.

 

[britannic]

Yeah, the cost of diesel and vehicles is a definite bummer! Have you seen any CTDs (apart from lorries) on the road in Cornwall?

 

[Crowhurst]

Britannic, just one in the past 3 years, a bronze colored 24 valve in the small town of Street, Somerset, where my mother lives. I was very surprised to see it. Not many folks want to spend $200 to refuel! Nick.