Is a revmax 700 as good as a Allison?

[jhenderson]

I really want my Cummins and 68rfe to work like it should!
I will start looking into purchasing a low stall converter and valve body along with new tuning.

I’m a die hard Chevy guy but when it comes to diesels it’s Cummins or nothing, I want my truck for pulling, reliability and power...not speed. If I wanted a fast diesel I would have bought a 6.7 ford.

Once again I love my truck, just want a better shifting experience.

You’ve already convinced yourself it’s not shifting “ As it should” . Wrong. It’s not shifting as you’d like. You’ll never be satisfied. Go back to your GM.

 

[SnoKing]

You’ve already convinced yourself it’s not shifting “ As it should” . Wrong. It’s not shifting as you’d like. You’ll never be satisfied. Go back to your GM.

He can even get a fake Allison in a 2020 GM.

 

[RVTRKN]

OP, this is why I didn't like my company owned 2014 2500 CTD 68rfe. Part of the issue is the 3:42 rear diff, and part transmission shifting strategy. The only way I could get it to feel more normal, is to paddle shift the trans. That way I could keep the RPM's at the optimum range the 6.7 likes. Keeping mine in T/H did nothing to keep the CTD at the right RPM at the right time. I never liked it, and the feed back here in TDR was not as expected as I thought, I always got the T/H explanation, and the 3:42 rear diff works great. If your willing to spend money on a delete losing warranty, then have the transmission custom built properly, with a 3:73 or 4:10 rear diff, or purchase the SRW 3500 W/Aisin. Have the dealer replace the 3:42 to 3:73 or 4:10 differential.

 

[Cummins12V98]

If he goes 3500/AISIN he will delete and have a whole set of new issues!!!

 

[Jim W]

OP, this is why I didn't like my company owned 2014 2500 CTD 68rfe. Part of the issue is the 3:42 rear diff, and part transmission shifting strategy. The only way I could get it to feel more normal, is to paddle shift the trans. That way I could keep the RPM's at the optimum range the 6.7 likes. Keeping mine in T/H did nothing to keep the CTD at the right RPM at the right time. I never liked it, and the feed back here in TDR was not as expected as I thought, I always got the T/H explanation, and the 3:42 rear diff works great. If your willing to spend money on a delete losing warranty, then have the transmission custom built properly, with a 3:73 or 4:10 rear diff, or purchase the SRW 3500 W/Aisin. Have the dealer replace the 3:42 to 3:73 or 4:10 differential.

For the 2018 and on model years Ram offers the 3:73 as standard and the 4: 10 as an option for the trucks now. I am not sure when this change took place but I think no one like the 3:42 gear sets.

 

[SnoKing]

And Ford and GM are going to 3.31s and 3.42s with new 10 speeds. 3.42 work fine in the RAM when mated to the Aisin's ratios. I think the switch to 3.73s is a concession to the 689RFE taller 1st and 2nd gear.

 

[amauri]

I'm going to have to stop reading these threads.
I had no idea the 68RFE in my 18 2500 CC was so bad

 

[SAP2018]

He can even get a fake Allison in a 2020 GM.

You guys are hilarious, if I wanted a GM I would go purchase it today.

I want MY truck to shift crisp, I’ll spend damn near whatever but it has to FIX the issue not just band aid it.

I do not like the fact that it will not downshift coming out of a corner, it will unlock 4th and slip the hell out of the converter then relock 4th when I step on the throttle, excessive throttle in 4th gear unlocked going like 15mph IMO.

If it’s completely normal for it to do that I will continue to throttle hard to pick up speed.

 

[SAP2018]

If he goes 3500/AISIN he will delete and have a whole set of new issues!!!

I don’t understand where all the delete talk comes from, I’m happy with my delete, I run a 30hp tune and drive normal, It shifted like crap when it was brand new also, I deleted at 700 miles because I don’t want soot in my new diesel.

I don’t need a 3500 or an aisin, I paid cash for my truck and will build a transmission if that’s what it takes. I don’t need a warranty department to help me repair my vehicles.

I ask questions because I value your opinion, I usually find the people on these forums very knowledgeable but apparently asking about a 68rfe brings out sour feelings.

 

[RVTRKN]

What is your rear differential ratio?

 

[RVTRKN]

The 68rfe is the red headed step child ever since the Aisin was available for the regular 3500 P/U. The Aisin was available in a 2007 & up, but in the C&C only, for a lot of years. The 68rfe is not as stout as the Aisin, but can handle the power of the Cummins, if its geared correctly. A buddy of mine has the same 2014 I drove, but in the Mega Cab, and loves the truck and thats pulling over the GCWR.

 

[SAP2018]

The 68rfe is the red headed step child ever since the Aisin was available for the regular 3500 P/U. The Aisin was available in a 2007 & up, but in the C&C only, for a lot of years. The 68rfe is not as stout as the Aisin, but can handle the power of the Cummins, if its geared correctly. A buddy of mine has the same 2014 I drove, but in the Mega Cab, and loves the truck and thats pulling over the GCWR.

I have 3.42, I plan on running 295/70r18 tires when my stocks wear out. I want to regear but with a 34” tire you think 4.10 is too much? Think 3.73 is more optimal? My 5th wheel weighs 9kdry and like 11-12k loaded.

When I purchased my truck I was well aware of the aisin, I plan on compounds and knew I would need a built transmission. What I wasn’t ready for was the weird lock up of the converter even with transmission tuning from DRD.

This week I’m purchasing an EZ Lynk and tunes from HPP/CTT tuning to try out unless someone says a valve body and revmax converter is my solution.

 

[RVTRKN]

I have the 3:73, but mine is the G56 manual, and wish I had opted for the 4:10. With a larger diameter tire, I'd opt for the 4:10. If you maintain stock diameter tires, then 3:73 would work as well.

I hated mine in 6th gear, allowing the 68rfe to choose the gear I needed, it would fustrate me to no end. The pinging in the CTD due to, to low of RPM at 50 MPH, and wouldn't downshift as I thought it should, was the pits. I even gave it time to learn my driving habits, which its supposed to do, didn't work either.

 

[Cummins12V98]

Throw in 4.10’s get a high quality rebuild and report back.

NOTHING wrong with the 68rfe. I towed 29k just fine.

 

[RVTRKN]

Sounds good to me.

 

[JR]

Have you spoken with Rudy at DRD about your issues? He seems like he supports his stuff and pretty knowledgeable on the tunes end at least. I don't know how much he knows about trans tuning but it would be one of my first calls if I were in your shoes.
Everyones perception of how a transmission should shift are different but what you describe doesn't sound normal. Maybe you can find a reputable transmission builder in your area to go for a ride with you before you pull the plug on it.

 

[mpaulson]

You could also try contacting Sonnax. They rebuilders and parts suppliers. I had a TCM from them on my 68 RFE in my 07.5 and it firmed up the shifts nicely in my modded and tuned 6.7 at the time.

 

[BigPapa]

Just to throw some names out there, there's been talk on CompD that Firepunk and Suncoast do well with the 68RFE builds and tuning.

 

[AH64ID]

Get the trans tuned better. There are countess tuning parameters for a 68. You need to find someone who does custom tuning, not just sell “boxed” delete tunes.

For the 2018 and on model years Ram offers the 3:73 as standard and the 4: 10 as an option for the trucks now. I am not sure when this change took place but I think no one like the 3:42 gear sets.

2018 was still 3.42’s only on SRW’s.

For 2019 the 3.42 was dropped and 3.73 is standard. 4.10’s are still a DRW only option.

My guess is that 3.42’s were dropped for tow ratings, but I’m curios what they’ll do for mpgs.

About the only option I’d like from a ‘19 is 3.73’s, but the 3.42’s are doing much better than anticipated.

 

[MRoberts]

The trans tuning from CTT is pretty sweet! It was between CTT and DRD, I chose CTT due to all of the positives I heard about their trans tuning.