Has anyone converted their 727 3-speed to an overdrive? If so, will the overdrive tranny bolt right in where the 727 was at or is there some type of mods that must be done? My truck is screaming at 70 mph and I would like to give her some room to run Any ideas of where I might find some pointers on the swap. Any info would be greatly appreciated. Thanks guys.

 

I don't now what it would caust but have you thought about a gear vender?

keep your tuff 727 tranny and add a tuff over drive to the end of it!

It $$$$ to buy, but i would amagan that the 46/47 over drive tranny,to have rebuilt,adaped and installed would be pritty close prise. just thout that i would give you a 2nt avanu or choise to ponder on!

 

Do a search, there have been tons of threads on this. You can do the swap. you can use a 518 with no lockup from I THINK 91-93, or use the 47RH from 94 and 95. The RH will give you the lock up and overdrive. You will have to add a lockup switch or a pressure switch to control the lockup and the OD.

 

Where could I find something like that?? Thanks for the suggestion!

 

In short, the gear vendors is a nice unit, installed it should cost you about 3-3.5K

 

This site has some good info, http://www.transmissioncenter.net/alto_3.htm, I know they're talking about converting a gas 727 to a gas A518, but its still informative.

I know that an A518 will bolt right up to the engine, the trans mount may require some modification or adjustment to accomidate the slightly longer tailshaft. Driveshafts will need to be shortened/lengthened(front only if you have 4x4) or donated from a donor truck. And you need a switch or some way to control the OD function.

 

Will the A518 splines work on my transfer case? I think mine has a 23 spline and some of the manuals have a 29 spline shaft. What does the A518 have? Thanks alot!

 

You are right, A518 has the same number of spines as your 727.

 

I'll dig up the internet sight when i get home but thay are cool!!

have been looking at them for years and mine arive to day so when i get it installed all let you no how it gos

there sales pitch is that that will hold up to 1200 horse power out of the box!!!!!

You remove the ext housing and bolt it up if is 2wheel drive or if it 4by4 it botls to the out put shaft of the t-case

 

Heres the link http://www.gearvendors.com/d2wd3s.html theres some cool chart there two

 

I checked out the website and it had what appeared to be a great overdrive system. But, would it not be more economical to swap the entire transmission? After all, my tranny has about 273,000 miles on it. I could pay for a remanufactured transmission and the labor to swap for what the gear vendor overdrive system costs. What do you all think? Would I be better off with the Gear Vendor overdrive or swapping transmissions. I would like to do the NV 4500 conversion but I think it will be too pricey for me. Let me know what you all think. Thanks alot guys.

 

MY TWO SENCE
My conversion to the get the gear vender is to save my "getrag"...and some better fuel milage.

the 727 is cheep to rebuild!(I have a 70 ply cuda that i race every season at RMR and started to have a lot of tranny probem,killed 3 of them and them fornd a guy that races at the track that rebuild race 727's and had him rebuild me one....it was 6 years ago and 6years of racing it every friday night! It still works grate!!)the tranny cost me $500.00and the 2tranny before cost me....well a lot more then that and were form 2 diff tranny shops.

With that said spend 3 grand on a 5th gear(gear vender) and if it you 727 dies
then you'll only be into it a 3,500...that is if you do all the rnr, he will only rebuild a tranny that is out and deliver to him!

Any of the chry over drive will notbe as strong as the Gear Vender.

thats my side of the fence.....next!

 

another option is to utilize your 3.07s with a MANUAL TRANSMISSION w/od for best economy and best highway gearing. I put a getrag in place of my 727 for lessthan half of what it would cost to put a GV in... the only real mod you need in addition to all the parts (I bought used resurfaced flywheel, and brand new sachs stock clutch, with used getrag rebuilt by myself) is to shorten the front driveshaft 2.5 inches.

 

If you threw a 47rh in there any Dodge dealer or tranny shop in the country would probably stock parts and know how to fix it if you got in a jam. The GV stuff only comes from them.

Just a thought!!

 

With a lot of help from this site. I put a 47RH in replace of my 727. I had to get a new trans to motor plate. Build/modify trans mount and cross member. Replace my starter with a newer starter and tweaked frame to get it to fit. I modified my dipstick tube using a 95 dipstick. Pulled the rear seal out of trany and used to silicone to seal transfer case to trany. Modified the shift linkage rod that is bolted to the frame. I think that is it for now!

Once again I would like to thank all those that help me succesfully make the swap.