47RH Shifting 2nd to 3rd Gear

[bigdan120]

Ok guys got my transmission together and now I am having an small issue.
The transmission seems to shift fine from 1-2 but 2-3rd has a 300 rpm jump up before it engages. Any idea how to fix?

 

[Big Blue24]

When your tranny does the 2-3 shift, it released the 2nd gear band thats wrapped around the direct drum and applies the clutches inside the same drum.

The servo that applies the band is the same servo that releases the band. The release fluid circuit is the same as the 3rd gear apply circuit.

Did you upgrade this servo with an aftermarket one, or did you put an upgraded Sonnax cover on this servo?

Did you change the stock 3.8 ratio lever to an aftermarket ratio probably 4.2?

When you rebuild the transmission, how much clearance did you leave in the 3rd gear direct clutch pack?

The RPM jump or (flare) sounds like the 2nd gear band is releasing before the 3rd gear clutch is applying and therefore there is a split second flare between the shift.

Adjusting the 2nd gear band adjustment on the outside of the transmission could help minimize the flare, however, if the servo is old, worn and leaky, or if the clearance in the 3rd gear clutch pack is too loose, it's always going to have a little bit of flare unless you tear it back down.

Another relatively easy fix if the band adjustment doesn't help would be to install a different ratio band apply lever. A 4.2 or 5.0 ratio lever will release slower than a 3.2 ratio lever which would make the tranny stay in 2nd gear just a hair longer so that 3rd gear can fully engage at the right time.


For starters, loosen the lock nut on the band adjustment lever on the driver's side of the transmission, tighten the adjuster good and snug, and then back out the adjuster 2 turns, finally hold the adjuster nut and tighten the lock nut. Take it for a drive, if it doesn't help, you could try playing with the adjustment (1.5 turns loose vs 2) but it probably won't totally fix the problem, just reduce it.

 

[zstroken]

When your tranny does the 2-3 shift, it released the 2nd gear band thats wrapped around the direct drum and applies the clutches inside the same drum.

The servo that applies the band is the same servo that releases the band. The release fluid circuit is the same as the 3rd gear apply circuit.

Did you upgrade this servo with an aftermarket one, or did you put an upgraded Sonnax cover on this servo?

Did you change the stock 3.8 ratio lever to an aftermarket ratio probably 4.2?

When you rebuild the transmission, how much clearance did you leave in the 3rd gear direct clutch pack?

The RPM jump or (flare) sounds like the 2nd gear band is releasing before the 3rd gear clutch is applying and therefore there is a split second flare between the shift.

Adjusting the 2nd gear band adjustment on the outside of the transmission could help minimize the flare, however, if the servo is old, worn and leaky, or if the clearance in the 3rd gear clutch pack is too loose, it's always going to have a little bit of flare unless you tear it back down.

Another relatively easy fix if the band adjustment doesn't help would be to install a different ratio band apply lever. A 4.2 or 5.0 ratio lever will release slower than a 3.2 ratio lever which would make the tranny stay in 2nd gear just a hair longer so that 3rd gear can fully engage at the right time.


For starters, loosen the lock nut on the band adjustment lever on the driver's side of the transmission, tighten the adjuster good and snug, and then back out the adjuster 2 turns, finally hold the adjuster nut and tighten the lock nut. Take it for a drive, if it doesn't help, you could try playing with the adjustment (1.5 turns loose vs 2) but it probably won't totally fix the problem, just reduce it.

Don't the higher ratio levers apply and release faster?

 

[Big Blue24]

Don't the higher ratio levers apply and release faster?

They apply and release slower.

The 4.2:1 and 5:1 levers give more 2nd gear capacity because they essential have a longer lever arm for more "leverage". The servo has to move farther before the band applies with higher than stock ratio levers.

Think of it this way, if you had an 8 ft long 2x4, if you put a log directly under the middle, 1' of movement on one end makes 1' of movement on the other and therefore 1:1 ratio.

If the center log was placed 6' from one end, 3' of movement would produce 1' of movement on the other end and therefore 3:1 ratio. A 10 lb weight on the 6' end would balance with a 30 lb weight on the short end.

Higher ratio levers have more leverage and therefore apply more pressure to the band at the expense of applying slower because more movement is required the higher the ratio gets.

Typically, high ratio tranny levers release too slow and cause bind-up issues with 2nd not fully released before 3rd is fully applied.

Bigdan's problem sounds like a flare not a bind-up problem, and that's why I suggested the higher ratio lever as a possible fix. Changing the lever requires removing the transmission so it's not an "easy" fix.

If this was my transmission, I'd definitely try playing with band adjustment before anything else.

 

[zstroken]

They apply and release slower.

The 4.2:1 and 5:1 levers give more 2nd gear capacity because they essential have a longer lever arm for more "leverage". The servo has to move farther before the band applies with higher than stock ratio levers.

Think of it this way, if you had an 8 ft long 2x4, if you put a log directly under the middle, 1' of movement on one end makes 1' of movement on the other and therefore 1:1 ratio.

If the center log was placed 6' from one end, 3' of movement would produce 1' of movement on the other end and therefore 3:1 ratio. A 10 lb weight on the 6' end would balance with a 30 lb weight on the short end.

Higher ratio levers have more leverage and therefore apply more pressure to the band at the expense of applying slower because more movement is required the higher the ratio gets.

Typically, high ratio tranny levers release too slow and cause bind-up issues with 2nd not fully released before 3rd is fully applied.

Bigdan's problem sounds like a flare not a bind-up problem, and that's why I suggested the higher ratio lever as a possible fix. Changing the lever requires removing the transmission so it's not an "easy" fix.

If this was my transmission, I'd definitely try playing with band adjustment before anything else.

I understand the leverage. I was thinking the 5:1 lever the servo had to move less for the tip of the lever to move more.

I agree he has a flare issue.

I don't have the multiple levers in front of me, but I was thinking the 2.9 lever for every mm the servo moved the tip at the band moved 2.9mm same with the 5.0 lever. Every mm of the servo the tip at the band moved 5mm.

Edit

Nevermind. I had the apply lever backwards in my mind.

46RE Rebuild - Opinions wanted - DodgeTalk : Dodge Car Forums, Dodge Truck Forums and Ram Forums

Here is a picture with some available apply levers.

 

[Big Blue24]

I understand the leverage. I was thinking the 5:1 lever the servo had to move less for the tip of the lever to move more.

I agree he has a flare issue.

I don't have the multiple levers in front of me, but I was thinking the 2.9 lever for every mm the servo moved the tip at the band moved 2.9mm same with the 5.0 lever. Every mm of the servo the tip at the band moved 5mm.

Edit

Nevermind. I had the apply lever backwards in my mind.

46RE Rebuild - Opinions wanted - DodgeTalk : Dodge Car Forums, Dodge Truck Forums and Ram Forums

Here is a picture with some available apply levers.

I can see the confusion, if you thought the short side of the lever contacted the servo instead of the long side.

 

[bigdan120]

When your tranny does the 2-3 shift, it released the 2nd gear band thats wrapped around the direct drum and applies the clutches inside the same drum.

The servo that applies the band is the same servo that releases the band. The release fluid circuit is the same as the 3rd gear apply circuit.

Did you upgrade this servo with an aftermarket one, or did you put an upgraded Sonnax cover on this servo? All aftermarket

Did you change the stock 3.8 ratio lever to an aftermarket ratio probably 4.2? Aftermarket 5.0

When you rebuild the transmission, how much clearance did you leave in the 3rd gear direct clutch pack? Um Dont remember LOL

The RPM jump or (flare) sounds like the 2nd gear band is releasing before the 3rd gear clutch is applying and therefore there is a split second flare between the shift.

Adjusting the 2nd gear band adjustment on the outside of the transmission could help minimize the flare, however, if the servo is old, worn and leaky, or if the clearance in the 3rd gear clutch pack is too loose, < Probably.. it's always going to have a little bit of flare unless you tear it back down. Not a problem Im getting good at this.

Another relatively easy fix if the band adjustment doesn't help would be to install a different ratio band apply lever. A 4.2 or 5.0 ratio lever will release slower than a 3.2 ratio lever which would make the tranny stay in 2nd gear just a hair longer so that 3rd gear can fully engage at the right time. Tried it if I tighten it any more it binds.


For starters, loosen the lock nut on the band adjustment lever on the driver's side of the transmission, tighten the adjuster good and snug, and then back out the adjuster 2 turns, finally hold the adjuster nut and tighten the lock nut. Take it for a drive, if it doesn't help, you could try playing with the adjustment (1.5 turns loose vs 2) but it probably won't totally fix the problem, just reduce it.

Thanks Guys!

What does the front band do and should I go for the 159.00 Front Kevlar or stock?
I screwed up the first time to many people and Beer and I put a valve in the valve body backwards lol and toasted my good band.......:nail: So should I go to the 4.2 lever after I check clearances? Could it be the valve body?
Shifts fine when letting it shift at 1800 rpms ...

 

[Big Blue24]

It is common to have bind up problems with the 5:1 ratio lever, that's why Goerend and a few others recommend the 4.2:1 levers.

I don't under stand how it binds when its a little tighter but flares when it's a little looser, would seem that if everything is installed correctly and band is not toast, there would be a happy medium between bind-up shifts and flare shifts.

How much pressure are you running in the transmission?

 

[bigdan120]

47RH

Yeah...I dont know....LOL Im going to run test maybe monday. I did notice that it was shifting better today and I did nothing.... I like doing nothing and things get better!