New single axel truck- engine, trans, axel ratio questions

[Hayman]

Hi I'm ordering a little peterbilt 335 for my farm. I pretty much looked at all brands in this class 33KGVW and they seem to come standard with some make of engine rated at 260hp/2400rpm and 620 lbs of torque. Of course you can up grade drastically depending on company. Peterbilt offers thier Paccar PX-6 ( the new 6.7 cummins ISB) or the PX-8 ( the 8.3 cummins ISC) in the 335's.


I went with the 6.7 cummins rated at 300HP/2600 rpm and 620lbs of torque@1600rpm. They suggested I go with the 6 fuller speed manual trans and an axel ratio of 4.11. I wanted to be sure I'm not reved out too high on the highway like my old truck. So then they suggest I go with the 6 speed fuller overdrive tranny and a 4.88 rear axel ratio. With this trans and axel combo this truck is suppost to cruise at 62mph @ 2000rpm down the highway. This seems to make sense as then I'd have a lower 1st and reverse gear with the 4.88 axel compared to the 4.11 or 3.90.

The truck will not be carring its limit in wieght ever but it will have to buck a lot of wind when loaded as the load sits high and is 10ft wide. Of course I have no way of test driving this truck as they don't have the exact one on the lot and it wouldn't have my hay mover rig set up on it anyway. But I guess it would be similar to a box truck for wind drag etc.

The present truck I'm using is a F700 ford with the 370 gas engine in it. I don't even know the hp, I imagine around 190-200hp?? The engine is underpowered for the job. On flat ground with no wind it can pull the load fine but I have my foot into it. It has the typical older truck low gearing so its just screaming (like 3000-3500 rpm)on the highway to get to 60mph. If there is any kind of head wind I have to pretty much stay home!

I'm hoping some of you guys have single axel trucks with similar gear ratios.

Do the specs the dealer has recomended sound about right?

They also tell me I should expect to double my fuel milage from 5mpg to about 10mpg.

[ksss]

I have similiar speced truck. I have an L-10 powered IH with a nine speed. 33GVW single axle. I am not that familiar with that particular 6 speed transmission. I will say that the setup I have, power is not a problem, no matter what I put behind it. The truck pulls it. I really like the 9 speed for this size of truck. I am not sure what the gear ratio is in mine. I guess I would favor more gears in a truck like your specing. It is much easier to find the right one when you have some options. A 6 speed is not offering much of a choice. You do have the hp to carry a 6 speed but you might get better economy with more gear selection. I guess you are somewhat at their mercy. Hopefully the sales guy knows what he is talking about. I don't know why you would push a 6 speed tranny in a 33K truck. However, I am not a Pete sales guy either.

[RockSet N' Grade]

Hayman.....I have a DT466 4900 with a 250 hp Navistar with fuller 6 speed. Can't remember the rear end ratio (will look it up and repost later), but with the 6 speed I am always hunting for more gear. I have thought about a two-speed rear end, different trans,....something. It always seems there is just not enough and the gears seem to be too far apart.If I do it again, I will opt for more gears and probably go with a 300 hp instead of the 250, even though the 250 is adaquate. The standard 190 hp just wont cut it (had one in this truck and swaped it out) unless you just drive around empty....then its fine. If they offer a jake brake as an option, I believe it would be worth it. What size axles? Is it a double frame? Air ride seat or bench? Air plumbed to the back or just electric?

[Hayman]

Hayman.....I have a DT466 4900 with a 250 hp Navistar with fuller 6 speed. Can't remember the rear end ratio (will look it up and repost later), but with the 6 speed I am always hunting for more gear. I have thought about a two-speed rear end, different trans,....something. It always seems there is just not enough and the gears seem to be too far apart.If I do it again, I will opt for more gears and probably go with a 300 hp instead of the 250, even though the 250 is adaquate. The standard 190 hp just wont cut it (had one in this truck and swaped it out) unless you just drive around empty....then its fine. If they offer a jake brake as an option, I believe it would be worth it. What size axles? Is it a double frame? Air ride seat or bench? Air plumbed to the back or just electric?


I have a 2 speed rear end now and I hardly use it other than when in 1st sometimes or backing into places. When on the road the 5 speed seems to work other than I could use another gear etc.

It's comes with air brakes, air seat, air ride cab, but no air ride suspension. I was just not sure how the air ride suspesnsion would be for stablity with the top heavy load I carrry and the places I have to get into.

Half the time the truck will be running empty back to the farm to get another stack to deliver.

I wanted a easy shifting standard so thats why I went with the six speed. Peterbilt doesn't offer the 7 speed but they do offer a 8 speed. I'm not sure if its a split high low or what like the 10 speed.

Ford offered a 7 speed spicer trans in their F750 I looked at. But I found best bang for your buck was the peterbuilt for what you all got. Ford was a little bit cheaper but the cab/seat was not as nice etc.

[Hayman]

I have similiar speced truck. I have an L-10 powered IH with a nine speed. 33GVW single axle. I am not that familiar with that particular 6 speed transmission. I will say that the setup I have, power is not a problem, no matter what I put behind it. The truck pulls it. I really like the 9 speed for this size of truck. I am not sure what the gear ratio is in mine. I guess I would favor more gears in a truck like your specing. It is much easier to find the right one when you have some options. A 6 speed is not offering much of a choice. You do have the hp to carry a 6 speed but you might get better economy with more gear selection. I guess you are somewhat at their mercy. Hopefully the sales guy knows what he is talking about. I don't know why you would push a 6 speed tranny in a 33K truck. However, I am not a Pete sales guy either.


Most of the companies seem to bring these little single axels in with the auto trans or a 6 speed manual. I haven't noticed any with a 9/10 speed other than if it was special ordered that way.

I'm no expert on these trucks so I really don't know how they should be speced other than what he sales guys tell me. I really should take a single axel box truck out for a drive if someone has one on the lot. That would be the best test I think as it would be pushing a lot of wind above the cab like my unit has to.

[Gravel Rat]

You made a big big mistake your going to HATE the truck get the ISC Cummins quit fooling around with that little engine that isn't designed for the truck you have. I'am not joking your NEVER going to get any resale out of the truck with a underpowered engine.

You had the salesmen talk you into something that is gov't spec'ed the salesman should be kicked right in the gonads. For a 33,000lb gvw truck you should have speced the truck with 8.3 Cummins power and 9spd. It may have cost more but when it comes to selling the truck its not going to loose 10 grand in price. NO owner operator will buy a underpowered truck like you ordered your stuck with that truck for life.

You put a load on that truck like max it out to 33,000lbs the truck is going to be so slow you will need a tractor triangle on the truck. I hate to be going down any hills with the truck you will burn out the brakes so quick because the engine doesn't have enough ******ing power even with a exhaust brake.

The 8.3 Cummins is tried and true its used all over and its a dependable medium duty engine. I would rather have a ISL in a medium duty but the ISC will do the job.

Good Luck I would be canceling that order your throwing money out the window.

[Hayman]

You made a big big mistake your going to HATE the truck get the ISC Cummins quit fooling around with that little engine that isn't designed for the truck you have. I'am not joking your NEVER going to get any resale out of the truck with a underpowered engine.

You had the salesmen talk you into something that is gov't spec'ed the salesman should be kicked right in the gonads. For a 33,000lb gvw truck you should have speced the truck with 8.3 Cummins power and 9spd. It may have cost more but when it comes to selling the truck its not going to loose 10 grand in price. NO owner operator will buy a underpowered truck like you ordered your stuck with that truck for life.

You put a load on that truck like max it out to 33,000lbs the truck is going to be so slow you will need a tractor triangle on the truck. I hate to be going down any hills with the truck you will burn out the brakes so quick because the engine doesn't have enough ******ing power even with a exhaust brake.

The 8.3 Cummins is tried and true its used all over and its a dependable medium duty engine. I would rather have a ISL in a medium duty but the ISC will do the job.

Good Luck I would be canceling that order your throwing money out the window.

Well I can still change the specs on the truck I believe in the next few days.

So you figure the 8.3 is the way to go....at what HP??? I wondered about going to the bigger displacement engine. But it seems all the trucks in this class come with the either the 3126 -7.2 cat, the 6.4 mercedesMBE 900 or the ICB 6.7 cummins.

As for load I'll never have it at 33GVW with what I haul. The F700 I have now is only rated at 25,000GVW. I think the new truck specs out at 10,000lbs, my stack retriever bed the mounts on the truck is about say 4000lbs and the stacks of hay would wiegh in at a max of 11,000 but typically there around 9000-10,000lbs. So the total GVW would be on average 24-25,000 GVW.

The thing is I "got by" for 9 years with the little 370 gas pot I have now. I just figured going to this 6.7 would be a big step up in HP and torque compared to it. Plus I'm gaining a gear with the 6 speed. I only had a 5 speed before and the problem was no high gear so the engine was screaming running back to the farm empty. Actually I just put the 370 back together again, it cracked a piston skirt but didn't score up the cyl. wall. So I'm going to retire it to a grain truck.

I know guys who have older IH DT466 engines and run a rig like I do and say they have enough power. I'm not sure though what their 466's are speced out at though. I'll look into more.

[2109 Stang]

Four years a go my friend was going to the same thing you are now , I commended a T300 KW with an ISC they wanted to givem an ISC with 240hp and 6 speed and can't remember the rear ratio , but he didn't wanted a dog so we ask what would be the difference on a 315 hp, it was only $700 but they still wante to spec a tranny that would put this truck at 2000rpm @60 mph I'd said why would you want to do that your wasting your money on the extra hp we went to a 10 speed and 390 rears ,the dealer said it will be to much ,they were very wrong that , thing does 60 at 1400 rpm and when you step on it goes like a bat out of hell and that is with a 590 super M with extendahoe four way bucket a/c cab, gross weight of 40,000 # that truck empty will out run any stock truck any time fuel mileage on stop and go trafic its about 8.5 to 9 mpg ,You cant go wrong with the ISC 260 to 315 and good tranny and rear combo ,its hard when you dont know ,becuase the sales man does'nt know either and I got a stinking feeling that they want to sale a package that gives them more commision but thats only my gut feeling .

[NateV]

The truck might be speced for what you need, but if you ever go to sell it you will have a harder time trying to find someone to buy it.

[snoope]

Hayman,

Nice choice in the "Petercar"...But try to push that salesman to "Give a little"...the ISC Cummins or a small Cat....And that 6 speed is tried and true BUT the allison auto and the Fuller 8LL are worth looking at....this leads to the rear-end gear choice...I have 4:88's w/my 8LL but my sister truck w/allison has 5:29's.....Like I said "Push" that salesman for details....he can run specs thru the computer for each option,even where the splits hit....

One of our major home heating oil companies specs the 335 only ,both propane and oil delivery..12 trucks strong ..replacing the 6 speeds with autos and the bigger motor...only complaint was these things take the driver in some places they should not be:laugh: :laugh: ...now they spec "Auto-chains" with them too:)

A few of the excavation contractors are up grading to the 335 w/cat 300 and that 8LL......Fully loaded w/ a machine in tow and no problems....

Only drawback is trying to polish them up so they look new all the time:walking: :laugh:


Snoope back quiet

[AintNoFun]

i have a pete 330 with the 8.3 cummins and a ford f800 with 8.3 cummins i believe as well.. both have allison auto 6 speeds.. not sure about the rears i'll have to check.. one truck is a hooklift with a 1200 gallon hydroseeder and the ford is always PACKED with b & b trees and weve never had a problem with a lack of power...

[start2finish]

you made mention that you wanted a "standard trans." I assume you mean fully syncronized.

If you will get accustomed to a non syncronized trans. you will love it, it gives you more gears and is designed for heavier uses. They are not hard to drive once you get the hang of it. as for speccing your truck, it is like building a shed or shop. It is never big enough. you will always outgrow it. you may one day wish to pull some sort of trailer. also if you have a larger engine it will not have to work as hard and in theory should last longer. 275hp would be my min. hp if I speced out a truck. by the way what is the pete and the ford come up to with the 2007 emmisions. price tag that is. just cab and chassis

[mow king]

I'd still stick to a manual. The allison automatics are real convenient when they're working...but when they go down, it's an arm and a leg to get it fixed. Also the Auto's tend to eat up a lot of power.

Trucking companies will many drivers have started to spec trucks with them because it's much easier to train a newbie driver on an automatic than a non-synchro manual.

If you can drive a manual proficiently, then I'd highly recommend that.

[Gravel Rat]

I would prolly go Cummins over Cat when your dealing with the smaller displacement engine if you go Cat. The ISC is built a little heavier than the C-7. If I was going with the 8.3 go with the the 315hp and 950ftlbs at 1300 RPM engine. The truck will be enjoyable to drive you will have lots of power you won't be constantly shifting. And when it does come to resale time anybody that needs a heavy single axle will buy the truck because it has decent power.

[Hayman]

Ok guys I did some more research tonight as I was going to head on down to dealer again tommorow. If the 8.3 is not a lot more $$ I was thinking I my as well go that route.

So I talked to a friend of mine who has a propane trucking company. He has a single axel IH with the 466 250hp and a 9 speed. He loads his truck right to the GVW limit 33K and likes all his gears. He figured with the 6.7 ISB and 6 speed trans the Pete would do fine for my needs as I don't load it up like his units..... But like others mentioned he said in no time I would come to really like a 9 speed. Plus he said in 5 years or something I may want to pull a trailer and the extra gears may come in handy.

So I then phoned another fellow with a hay moving unit just like mine who runs an early 90's GMC Topkick with a Cat. I found out his is an auto trans and a little 3116 Cat motor rated @235hp!! Now I know nothing about this engine but he says power is really not an issue as it cruises down the highway at 60mph no problem any day of the week!!! So I unless these 3116's were some fantastic under rated hp motor I should be fine with what I got speced out now.

I'm still going to talk with the sales dude again though and check pricing on the other engine & trans. Resale is really not an issue unless I quit my business or something which I don't plan to do. But even then I would sell it equipped with my stack moving rig on the back.

Thanks for all the input it really helps to throw around ideas I never thought of before!

[Gravel Rat]

The problem with the 6.7 Cummins for one its not proven yet like the 5.9 its a new block design etc so who knows how well its going to perform. Its a siamese block like the old 400 Chevys not good.

The ISC is a proven engine even if you only get it at 250hp rating its far better than a smaller engine trying to do the same.

I don't even know why Paccar even offers the small Cummins as a engine option in trucks even schoolbusses don't have small engines anymore the Blue Bird Vision has a 35,000lb gvw.

[Hayman]

The problem with the 6.7 Cummins for one its not proven yet like the 5.9 its a new block design etc so who knows how well its going to perform. Its a siamese block like the old 400 Chevys not good.

The ISC is a proven engine even if you only get it at 250hp rating its far better than a smaller engine trying to do the same.

I don't even know why Paccar even offers the small Cummins as a engine option in trucks even schoolbusses don't have small engines anymore the Blue Bird Vision has a 35,000lb gvw.



I checked and to go to the 315hp 8.3 its another $4400 plus I'd have to upgrade the trans I would think to handle the torque of it. I forgot to ask them about the upgraded trans costs etc. Sounds like though it would push me well over $70K which I'm not prepared to spend on this little hay moving truck. Its kinda over kill as it is already, I don't put the miles on it like someone in a comercial buisness etc. I figure it should last me 20 years no problem and by then who knows what fuel we'll be running!

I'm quite interested to see what kind of milage its going to get as the guy I talked to with the topkick with the auto/cat says his worked out to 10-11 miles per gallon on average.

Man if I can get even 10 mpg and at the lower cost I pay for farm diesel on average compared to gasoline I could save $1000's every year on fuel costs!

[Gravel Rat]

I would look for a preowned truck there is lots of them out there. You are also looking at one of the most expensive brands on the market. I imagine Kenworth is cheaper than Pete.

I can safely say your not going to like the low powered truck I would say go with the 6.7 Cummins if you were buying a 3 ton truck with a light gvw then it would be okay.

I guess I'am used to living and driving in B.C. you don't buy low powered medium duty or tandem axle trucks. Old gas pot medium duties are few far and between even farmers rarely use them.

As for saving money on fuel it depends on how many kilometers you run in a year. A gas pot medium duty isn't a option for us because its not enough power.

International is prolly the most popular medium duty truck along with Freightliner. Its very rare you see a Pete 5 ton unless its a owner operator tow truck or something similar. A tandem axle is a better option they are cheaper to find and you can haul more. If your running a 20 foot flatdeck on a single axle you might aswell go with a tandem. You can haul 12 tons on a tandem instead of 6 on a single axle.

[start2finish]

gravel rat, this guy is hauling hay. a tandem??

[Gravel Rat]

You buy a tandem put a 24 foot bed on it then you have a trailer to haul even more. Most hay hauled in B.C. is on B trains or flatdeck trailers.

[Hayman]

I would look for a preowned truck there is lots of them out there. You are also looking at one of the most expensive brands on the market. I imagine Kenworth is cheaper than Pete.

I can safely say your not going to like the low powered truck I would say go with the 6.7 Cummins if you were buying a 3 ton truck with a light gvw then it would be okay.

I guess I'am used to living and driving in B.C. you don't buy low powered medium duty or tandem axle trucks. Old gas pot medium duties are few far and between even farmers rarely use them.

As for saving money on fuel it depends on how many kilometers you run in a year. A gas pot medium duty isn't a option for us because its not enough power.

International is prolly the most popular medium duty truck along with Freightliner. Its very rare you see a Pete 5 ton unless its a owner operator tow truck or something similar. A tandem axle is a better option they are cheaper to find and you can haul more. If your running a 20 foot flatdeck on a single axle you might aswell go with a tandem. You can haul 12 tons on a tandem instead of 6 on a single axle.


At first I was really set on getting an IH or Freightliner but they were both more $$ and didn't seem to want to deal. Its been 2 weeks and both salesmen never bothered to get back to me. The Freightliner salesmen was alright but busy as hell . The IH guy really didn't seem to want to waste time talking to me at all. It was here is the price take it or leave it cause the truck will sell no problem it you don't want it.

I also priced Sterling, Hino, Kenworth, Ford, and GMC Topkick.

The Peterbilt came in at the best price and bang for your buck by far.

kenworth was $6K higher but he did get back to me with a lot better price a week later. But still said he couldn't match the peterbilt quote.

I did find a new 06' Topkick that had been sitting on a lot for so long the front chrome bumper was starting to rust! It was cheaper in price ($1400) but also came with a lot less. Plus I really didn't like the cab set up, mirrors or Cat engine.

I live in Alberta here and the economy is just nuts. At the truck dealers the salemen seemed to be run off their feet except maybe at Hino it was more relaxed. Most times when talking to salemen they would have someone waiting to talk them and their damn ph. ringing constantly. One day at Peterbilt when I was talking price with the guy he had 3 customers lined up waiting to talk to him about buying a truck and people on hold on the phone!

Maybe I would have got a better price quote out of province???

As for used trucks I've looked for years for something. The older ones at farm sales (with grain boxes on them) that have lower Kms like pre 1990 all seemed to be geared too darn low like 55mph. Newer then 1990 farmers didn't buy much for diesel single axel trucks anymore they went to tandems. The used truck lots have lots of stuff brought in from down east and some stuff is not too bad. I found first off the axels were always in the wrong place. Then they typically wanted a lot of cash for some old truck (junk)that looked like it was in the Golf war! You can't get much for 10-$20K on the used truck lots unless your prepared to spend alot more cash and time going over it. Been there done that in the past with the last couple trucks. It is an option for sure but for this one I wanted something nice.

A tandem wouldn't really work for my stack retriever set up. This thing doesn't have an actual flat deck on the back. Its hard to explain how it works, its self loading and unloading you'd have to see a video or pictures of it I guess. I have 3 remote joy sticks mounted in the cab to operate it all.

I don't know but I really think going to a big block might over kill for this thing. At least thats what guys "who actually run them" tell me. I don't think its real good to have a large engine and not being able to work it once and a while either. Don't forget this thing is not going to be loaded down always like a highway tractor. 50% of the time its running empty with no load on it. We'll see in April onces I get it rigged up hopefully I won't be disapointed.

thanks for the input!

[Gravel Rat]

I seen in your signature you are from Alberta and the economy is doing allot better than B.C.s . I heard trucks are not cheap in Alberta now because the demand for them is there. I know guys selling tridrive Kenworths here in B.C. are selling used trucks from B.C. at unbeleivable prices more than what guys here are paying for them. There was such a demand for tridrives Alberta companies were buying up used tridrive logging trucks. There is a Richie Bros coming up this month in Chilliwack that has a few tridrive Kenworths in it I bet all the trucks head to Alberta.

Anyhow good luck with your truck I have a idea how the loading system you have I seen bail decks on the internet.

[Greybeard]

Hayman - You're going to love that Pete. We have a 330 with 230 HP Caterpillar 3126E, Fuller 6-speed and 4.11 rear end. Plenty of power, even when loaded at 30,000+ pounds. It governs out at around 64 mph on the highway at 2200 RPM, and I've gotten 10 mpg cruising at 55. Keep it greased, change the fluids and filters and it'll outlast you. The nice thing about the smaller Peterbilts is that they share so much with the big rigs, like riveted aluminum cab and heavier frames and chassis components. Check out some of the older Pete tractors on eBay - a million miles isn't unusual.
How much is a bale of hay selling for in Alberta? I haul some here for my sister and her horsey friends. Good luck.

[Hayman]

Hayman - You're going to love that Pete. We have a 330 with 230 HP Caterpillar 3126E, Fuller 6-speed and 4.11 rear end. Plenty of power, even when loaded at 30,000+ pounds. It governs out at around 64 mph on the highway at 2200 RPM, and I've gotten 10 mpg cruising at 55. Keep it greased, change the fluids and filters and it'll outlast you. The nice thing about the smaller Peterbilts is that they share so much with the big rigs, like riveted aluminum cab and heavier frames and chassis components. Check out some of the older Pete tractors on eBay - a million miles isn't unusual.
How much is a bale of hay selling for in Alberta? I haul some here for my sister and her horsey friends. Good luck.


Greybeard,

thanks for the info!

The one I have ordered is geared just a bit higher then yours at 65 mph its suppost to run at 2045 rpm. I'm not as loaded and have a bit more HP so it sounds like it should work ok. All my hay is sold for the horse market. I sell different grades of hay, the good stuff this winter has been selling for $4 a 55-60lb bale.