New member, old trucks.

[Waystro]

Cool SA here but working in East Tx around silsbee. Like I said I got a sterling with 3.55s Srw with 160k of you want to trade them let me know.

 

[SirRea63l]

Cool, I will send PM.

 

[LCAM-01XA]

I am looking at gears for the axles. Axle is a Ford/Sterling C5 with 4:10's, I assume it is the same axle set for both so I can order two sets of gears.

You're talking about regearing both trucks? They actually have different gearsets from the factory, however they are interchangeable. The '94 gears are better design in that they have stronger coupling to the yoke for the driveshaft. If you're about to order two identical sets of gears do make them both for a '94 truck, then your '91 will get a nice upgrade. However do keep in mind the newer design gears will need a newer-style yoke as well. Front axles are Dana 60 in both trucks, and those do take identical gears (assuming both trucks are 4.10-geared now), you can order two sets of the same kind for them no problem.

The big decision will be 3:73 or 3:55. My gut says go with the 3:55's as this truck will be mostly a highway truck. It rarely ever does towing duty but I will tow an 18' bumper flat bed trailer, nothing very heavy, and the heaviest thing will be a 3500# tractor. I am looking mostly for fuel economy, with the 4:10's first gear is useless to me, it starts out easily in second, I have to keep it floored to even see 70 mph, and that has to be fixed.

Go 3.55 and don't think twice. The 3.73 will only raise your cruise speed by about 5mph, IMHO hardly worth the expense of purchasing new gears and having them installed. The 3.55s will give your roughly 10 mph faster road speed, bit more noticeable in the MPG department.

Does anyone regret going to 3:55's with the ZF-5?

Yup, I do. Actually what I regret was installing a factory diesel-spec ZF in a truck with 3.55s, for our yard goat needs 1st in high range was too high and reverse was even worse, and being stuck in low range all the time does get annoying after a while. Remedied that with a wide-ratio ZF so we can putt around in high range most of the time, much better for my sanity. Naturally there is no free lunch, the price for having both low gears and nice overdrive is the engine speed gaps between the gears that can hit 1000 RPMs - most folks would hate driving something like that, if you ever drove a 70s Ford with a creeper 4-speed imagine that with your engine under the hood. Point is, you may wanna consider leaving your water truck with 4.10 gears and just replace the E4OD with a standard diesel ZF (if it needs it) and call it good. For the truck that goes on the interstate and doesn't spend much time crawling around your property ZF with 3.55s will be pretty great.

 

[SirRea63l]

Thanks, actually I am only doing the 94, the water truck may never hit the highway ever again and it needs to do grunt work on the farm. The same axle set meant that both the front and rear should be the same gear set. Ford seems to have done a lot of mix-n-match combo's over the years so I just wanted to make sure. I expected them to be the same, but also didn't want any surprises.

Thanks to everyone for confirming the 3:55's are the smarter move. I also found another brand option, OEM which I didn't expect to find. It was claimed they are quieter, which I found amusing since this is a noisy mechanical diesel, I doubt I could hear it if it whined like crazy.

 

[LCAM-01XA]

Thing with Fords is that since the mid-70s the front and rear axles use different gear sets even if they are the same axle (say Dana 60s). The reason for this is the front axle is a high-pinion design, so it's not essentially a rear diff turned around and driven in reverse - the gears for these are actually a mirror image of the standard rotation rear axle gears, they are referred to as "reverse-cut" gears. So basically even if your truck did have the same series of axle front and rear you'd still be buying two different gearsets. For this particular truck you need 3.55 gears for a long-pinion 10.25" Sterling rear axle and 3.54 reverse-cut gears for a Dana 60 with a 4.10-down carrier. If in doubt post links here to the gears you're looking to buy and the collective will verify if they are indeed what you need

 

[SirRea63l]

That makes sense, as time permits I will do some more shopping and report back. I did learn about the yoke differences and I am actually considering the OEM set found here...
http://eastcoastgearsupply.com/c-61...spider-gears-ford-ford-10-25-inch-10-1-4.html
I will probably call when the time comes to make sure they send the right stuff. Summit and a few other places have decent prices as well.

 

[riotwarrior]

In stock
3.54 RnP D60
3.55 RnP Sterling 10.25 short yoke

Make an offer

 

[LCAM-01XA]

That makes sense, as time permits I will do some more shopping and report back. I did learn about the yoke differences and I am actually considering the OEM set found here...
http://eastcoastgearsupply.com/c-61...spider-gears-ford-ford-10-25-inch-10-1-4.html

You mean these here critters:
http://eastcoastgearsupply.com/i-19221809-ford-10-25-original-equipment-3-55-ring-pinion.html
I'd buy them and don't even think twice. Factory gears have proven their strength and reliability over millions of cumulative miles travelled by all the trucks that run them, IMHO this is the safest bet and the price is pretty good as well.

As for the yoke, you reuse what you have now. Your truck already runs the updated design gears from the factory, I see exactly zero sense in buying a new yoke that will be the same as your factory one. Yokes are not exactly a wear item, so if yours is in good shape (and it should be) just run it with the new gears.

Then for the front you'll need one of these:
http://eastcoastgearsupply.com/c-25...ion-d60-reverse-dana-60-ring-and-pinions.html

Again I'd suggest the OEM gearset but at $405 it may be a bit hard to swallow... Heard mixed reviews on the Motive gears, for a truck that is not a weekend play toy I would probably skip them in favor of Nitro. Btw the owner of Nitro is a pretty cool guy who will answer tech questions even if you don't buy from him, at least that has been our experience. ECGS do have a pretty solid reputation as well, so I think either vendor will steer you right when it's time to buy.

 

[SirRea63l]

Yes, that is what I was looking at. I did not find a Nitro in the 3:54R and yes the Dana/Spicer is spendy but I have no complaints about the OE stuff. I have to call around and see who locally can correctly do the swap.

 

[riotwarrior]

Mine are used OEM...however very nice shape...250 for both sets shipped on yer dime....

Just saying....

 

[SirRea63l]

Isn't the yoke different or do I have it backwards?

 

[riotwarrior]

I will include yoke

 

[SirRea63l]

Won't that mean a different driveshaft as well? Won't a shorter yoke mean the driveshaft will then be too short?

 

[riotwarrior]

Will measure yoke and compare iirc 1/4"

 

[LCAM-01XA]

Won't that mean a different driveshaft as well? Won't a shorter yoke mean the driveshaft will then be too short?

You'll be fine. We recently dropped in a new t-case that shortened the rear shaft by whole inch and got it right where I think it's darn near perfect - meaning up until now it was a full inch longer than ideal, and it didn't care on bit, no vibrations or anything.