gearvendors o/d

[cozadlance2]

so, some here like the gearvendors o/d unit. some do not. i feel that it likely comes down to what it can do under the conditions it is subjected to and i request opinions. from what i have read, it works decently if never asked to uphold the rather extreme durability claims that gearvendors makes for it (marketing.) This being said, please see my dana60/9inch post and come on back here and tell me if a guy wanting to bring the rpms down to 2400 or so at 60 m.ph. in a 1971 f250 2wd with a 360 2v and a C6 running 245/75/r16s and a dana60 3.73 would succeed with a gv o/d or perhaps something else? Also, is o/d something i should consider if i am EVENTUALLY hoping to swap in a t18/19? thanks again .

[mlheppl]

At $3K for the gear vendors unit, personally I don't see the benefit. With a c6 and your 3.73 gears, you're turning just over 2800 rpm at 65mph. Dropping own to 3.54 gears would put you at around 2680 rpm. You could drop your rpm's down to 2575 with the 3.54 gears and going to a tire like the 235/85/16's. Tires and gears would cost you less than half of what the gear vendors OD unit would cost.

[averagef250]

At $3K for the gear vendors unit, personally I don't see the benefit. With a c6 and your 3.73 gears, you're turning just over 2800 rpm at 65mph. Dropping own to 3.54 gears would put you at around 2680 rpm. You could drop your rpm's down to 2575 with the 3.54 gears and going to a tire like the 235/85/16's. Tires and gears would cost you less than half of what the gear vendors OD unit would cost.

Exactly.

[cozadlance2]

duh.
i see. the fog is lifted.
thanks. really. i can be dense sometimes.

[mlheppl]

Don't feel bad, I was asking myself many of the sme questions (along with asking here). Looked at overdrive units, overdrive trannys and finally came to the conclusion that I could reach the same results with gears and tires. Save myself a pile of money and time/effort in the process too.

Here's a cool link to a calculator that will let you play with different variables to help you to make your own decisions.
http://www.grimmjeeper.com/gears.html
You can change trannys, gears, tire sizes, overdrive units etc... Put your current setup in one column and make changes to your setup on the other column. Then you can see side by side what differences you'll achieve by changing differen't components. The calculator is set up for 4X4's so for 2wd vehicles just put in 1.00 for high and low range in the transfer case section.
Mike

[robroy]

Hey CozadLance2!

Like Mike's saying, there's no special reason you should have been aware of this viewpoint on the GearVendors device; I don't think it's common knowledge. And in fact, although I'm not necessarily one of them, some folks aren't in agreement that differential ratios and tires are a better solution for our trucks. There have been a number of threads on this subject.

This said, considering the wonderful simplicity of the differential ratio and tire solution, it would seem favorable to me (if it'll give you the results you're looking for). I was initially looking at the GearVendors device also, but am now planning on a differential ratio + tire solution.

Robroy

[cozadlance2]

Thx guys. Just looking to ease her typical day's work till she is feeling her absolute best.
She is semiretired currently. Putting around surface streets with limited freeway use. She has become a dependable dd and I want her to take it easy till most of her wounds are healed from her previous owner. Not meaning to badmouth. I was 17 once too.

[GSequoia]

Does anybody here run that expensive OD? I'm curious because one day I wouldn't mind OD since I don't want to lose my 4.10s for towing.

I'm curious how well it is liked, in a load hauling environment (trailer would be about 5,500 lbs loaded) aside from the rather steep asking price.

Thanks

[averagef250]

Does anybody here run that expensive OD? I'm curious because one day I wouldn't mind OD since I don't want to lose my 4.10s for towing.

I'm curious how well it is liked, in a load hauling environment (trailer would be about 5,500 lbs loaded) aside from the rather steep asking price.

Thanks

The GV works just like any other add on overdrive with the added feature of not having to shift a lever or deal with air/vacuum/electric mechanisms. My experience not owning them, but dealing with customers who have them is individuals with lightly loaded pleasure type vehicles like trucks that cruise empty, small motor homes and the like get long fruitful lives from a GV. The guys that use thier trucks like trucks and tow regularly or larger motorhomes wear them out rapidly under weight and power approaching the max ratings of the unit (say something around 5000-10K miles) while guys that occasionally tow trailers, but mostly light foot it around get 50K or more from them.

I have mentioned a bellhousing graft before, but feel this may be a good time to mention it again.

FE's are limited, for that matter all engines are limited for options of installing a good all hydraulic (no computer) automatic transmission with overdrive and a lockup torque converter. There is the Ford AOD (A pile of poo poo), The GM 700R4 (another pile of poo poo) and there is the Dodge 47RH. These are the only american automatics ever made with these criteria.

Before anyone goes apesh*t bananas over putting a dodge part under thier Ford consider these facts- How many guys swap NV4500's under their trucks of all types? Those are mostly dodge units. GM made maybe 1/5 the number of stick NV4500 trucks as dodge did. The 47RH is a beefed up modernized 727 automatic. Most of it's parts are direct 727 pieces. IH and AMC used millions of chrysler 727 autos under thier cars and trucks.

Thinking about all this stuff do you ever wonder what a GV overdrive really is? Maybe it's the overdrive part from a newer automatic from chevy or ford? Nope. Maybe it's an overdrive unit they built from scratch to be super bulletproof, stronger than anything else out there like thier advertizing states? Nope. The GV overdrive is a 1960's VOLVO car overdrive unit stuffed in a neat little aluminum casting.

You want a killer automatic behind your old FE with an overdrive to make a GV cry have a bellhousing graft done on a 47RH with one from an FE C-6 and viola! You got it for, including the cost of a high quality rebuild, probably a lot less than $2000 depending how wild you get with go-go goodies in the tranny.

You also have the added benefit of no GV controller box. No more $1500 rebuild from GV with no parts support or availability from anyone but GV. With the 47RH you have an automatic that in the off chance you do have a failure in timbuck nowhere any tranny shop out there has any part needed to fix it on the shelf.

Kinda cool huh?

[happycamper]

cozadlance...... Would that be be Lance Cozad? If so, then greetings from Lee Cozad.

[Racer Z]

* 1st; 2nd; 3rd; 4th; : Gear Ratios
2.46; 1.46; 1 .; n/a; : Ford C6
2.45; 1.45; 1 .; 0.69 : Dodge 47RH

Same gear spread. 4th is practically a complete gear change.
At 70 MPH 1:1 is 5600 rpm and 4th would drop the revs to 3860. That's using my existing 11.5 x 16.5 tires and 4.10 rear end. That would certainly be nice on the flats while lightly loaded.

Do you know if this has actually been matched up to an FE block?
Any idea how they did it?
Any idea how efficient the 47RH is? Rumor has it the C6 is terrible.

[cozadlance2]

Lance Cozad I am. Hello Lee. My parents were Marjorie and Kenneth Cozad.

[averagef250]

* 1st; 2nd; 3rd; 4th; : Gear Ratios
2.46; 1.46; 1 .; n/a; : Ford C6
2.45; 1.45; 1 .; 0.69 : Dodge 47RH

Same gear spread. 4th is practically a complete gear change.
At 70 MPH 1:1 is 5600 rpm and 4th would drop the revs to 3860. That's using my existing 11.5 x 16.5 tires and 4.10 rear end. That would certainly be nice on the flats while lightly loaded.

Do you know if this has actually been matched up to an FE block?

I've done a 47RH/IH graft and measured for an FE graft, but customer chose to purge the FE and go Cummins.

Any idea how they did it?

Using a mill and a TIG welder.

Any idea how efficient the 47RH is? Rumor has it the C6 is terrible.

I don't really know where the ratings come from for auto efficiency. I don't know where any of the chrysler 727 variants stand, but they were used in production well into 2004 in 48RE clothing. They're a beefy tranny, same size components as a C-6.

[Racer Z]

* 1st; 2nd; 3rd; 4th; : Gear Ratios
2.46; 1.46; 1 .; n/a; : Ford C6
2.45; 1.45; 1 .; 0.69 : Dodge 47RH

Same gear spread. 4th is practically a complete gear change.
At 70 MPH 1:1 is 5600 rpm and 4th would drop the revs to 3860. That's using my existing 11.5 x 16.5 tires and 4.10 rear end. That would certainly be nice on the flats while lightly loaded.

Do you know if this has actually been matched up to an FE block?

I've done a 47RH/IH graft and measured for an FE graft, but customer chose to purge the FE and go Cummins.

Any idea how they did it?

Using a mill and a TIG welder.

Any idea how efficient the 47RH is? Rumor has it the C6 is terrible.

I don't really know where the ratings come from for auto efficiency. I don't know where any of the chrysler 727 variants stand, but they were used in production well into 2004 in 48RE clothing. They're a beefy tranny, same size components as a C-6.

Yeah, I found a few pictures and they both appear to be similar in size and shape. The 47RH is plenty strong to handle my needs and the upper limits of my F250 390/C6. Looks like it wouldn't be to hard to make an adapter plate. Have the drive shaft redone.

[averagef250]

You can't make an adapter plate. I'm talking about milling off the 47rh bellhousing, milling off an FE bellhousing and welding one onto the other while maintaining alignment and proper depth. Drill the converter pattern in the FE flexplate and turn a bushing for the converter pilot in the crank. Use a V10 converter.

An adapter plate is impossible because of starter location. Dodge starter's on the left. Ford starter's on the right. If you try to run a right side starter on a bellhousing for a left side starter you have a starter that runs into the bellhousing.

This isn't a big job if you have the right tools. The thickness where the weld goes is under .150-.200", clean tranny cases weld very easily. a tight, well trammed mill with a good DRO does most of the work. Cut the bellhousings in a big bandsaw if you have one. A skilsaw works great too.