My Transmission has me Worrying...
 

Hey guys!

So, I have a 2005 Cummins with a 5 spd Automatic in her! And she shifts pretty solid from 1 through 4, but going into 5th (or is it called Overdrive...?) SOMETIMES is a little scary.

It seems under anything over like a 40% throttle load it, almost like feathers itself into gear. It hesitates shifting. If I back off before it gets there it goes right in smooth no problem.

So I'm wondering what would cause this...is it maybe supposed to do something like that? Is it feathering itself in because it's such a huge change in gear ratio? Or should I start saving my money for a rebuild or at least some beefier parts?

Thanks guys!

PS: I plan on upgrading the tranny anyways. Someday Id like to hit 500hp...so what's the cost on getting a tranny to safely handle that number? Any Thoughts?

Sounds like your converter is on its last leg.

Well I had mine built last October and it ran me 4,700 dead washingtons, and some change. Mine can handle up to 700 ponies though, but Im in the 360ish hp range. What do you plan to do with your rig...heavy towing, sled pull, race, etc?

Oh boy here we go. :humm: As for plans all I want is something reliable for the occasional trailer pulls while sill handling being my weekend toy and daily driver. Possible 500hp goal. My mom and Girlfriend are both into horses and have a gooseneck two horse trailer with a living quarters. Empty is 3600lbs then two horses and tack could be close to 3-4000 extra lbs. So possible up to 8-10,000 MAX! Thanks for the reply by the way!

Oh and also my avatar is a picture of me hauling a ford that had bad injectors so it was kinda important we didn't drive it obviously! That would probably be the heaviest it ever hauled! Thinking that was almost if not over the 10,000lbs mark!

Haha, what a coincidence! I once had a ford PSD that spent a lot of time being towed also. That's the reason I own a Dodge CTD now. Well, looks like youre gonna be working your rig for sure. In that case, you should have your trans built rather stout, to handle all youre gonna throw at it. That's gonna be pricey. Or, you can buy a ready built trans, also pricey. Really depends on what you want to do. The sky is pretty much the limit........so is the budget.
I had mine built to handle a hell of a lot more than I could ever throw at it. For me, more is better......but at a cost. The heaviest Ive towed so far is my travel trailer, at just over 10k lbs. My rig pulls it like its not even there, and my trans is happy to work.

If your gonna work it hard, don't skimp on just a basic rebuild, as you could regret that in the future with another rebuild (past experience talking here). Take that bite out of that sh*t sandwich now so you don't have to stand in front of the sh*t buffet later. :c: Cheers!

I appreciate all the advice Redd! Honestly I'm back in Japan now so the truck is sadly parked until I get back! So I have some time to start saving now! I'm hoping I have enough saved up to just build up the tranny when it goes (hopefully before) but I don't want to do a basic rebuild for the reason you said. I look forward to my adventures now in the Diesel world. It's always been a dream of mine to own my own Diesel and begin modding it and having fun with it! So now I'm gonna save my pennies and build my dream truck! Cheers to you to my friend! :c:

One more quick question! Where did you have your tranny built at? Just a local shop or what was your story with that! Thanks man!

No problem. This is what we members are here for. I have a good friend that owns a tranny shop, and he mainly builds high performance, various race, and crawler transmissions for a wide range of applications. He guarantees his work and has a grat reputation here in El Paso, TX.
Thanks for your service, and stay safe.:c:

I hate to break this to you but the 48rfe is only a 4 speed.... the "extra" gear you're probably feeling is either the bands or converter lock up, but she's only got 4 gears:argh:

that being said Bigg Redd is right, save your pennies and build it right the first time, so that hopefully its the last time

I do highly recommend doing a billet input shaft tho, its the one thing i would recommend as a minimum, theres also the intermediate and output shafts that can be upgraded too, but as just the input shaft is around a grand thats probably where you could stop

Suncoast makes nice kits for rebuilds, and ive heard good things about PPE's kits(at least for the allison)as well

but I'd look into finding a reputable shop to build it and make sure they use high quality components too

I know of at least one shop down there in Iowa that I have heard are one of the best out there

PM me if you want to know more since im not sure if they're a vendor here and I don't want to step on toes:c:

Hey That's what I'm here for! To learn these things! And I saw you mention a shop in Iowa but the truck lives in Michigan! SO I'd be trying to find a shop around there when the time comes! If you know any shops up here let me know! Thanks again! :c:

Only good diesel shop that I personally know of is Merchant Automotive, but they're pretty much Duramax exclusive

Just look into Goerend transmissions, best of the best as far as I know, but I've been out of the dodge game since 08:w2: