H55f on 2F help! (1 Viewer)

[Tylerh84]

Alright, so I have been digging around and I am pretty sure something is up.

So I have a 2F with a H55 installed from PO. My question is where should I be speed/RPM wise. I'm pushing 4k in 5th just to do 60mph. I'm fairly certain that the diffs have been geared down for larger tires because I am always about 5 under what my tach says but that doesn't affect the tach readout.

Any ideas?

 

[Casey E]

Sounds like 4.88 gears if your on stock tires. You can do the math buy useing online calculators and imputing your tire size,tranny and gives rpm. Should be able to change inputs to match what you have going on.

 

[mattressking]

That's extremely high for 5th. From what I understand, 5th with roughly 33s puts you around 2500rpms at 70.

What size tires?

Are you sure you're in 5th?

 

[Tylerh84]

That's extremely high for 5th. From what I understand, 5th with roughly 33s puts you around 2500rpms at 70.

What size tires?

Are you sure you're in 5th?

I'm on 31's and I know I'm in 5th

It is extremely high which is why I'm consulting the group for some help. I'm thinking maybe there was a gear reduction done at some point maybe in the transfer case?

 

[Casey E]

Is your transfer in 2HI

 

[mattressking]

Is your transfer in 2HI

Exactly, my next question.

 

[Tylerh84]

Is your transfer in 2HI

Yes transfer is in 2HI I have wheeled it a couple times and had it in 4LOultiple times and am definitely in 2HI

 

[Casey E]

Ok with axle gears in the 4.88 range and 60 with say 31's you should be pushing 2500 rpm max.

 

[Casey E]

So what size tires ? I need this input since we know the tranny is .84 or so in 5th.

 

[Casey E]

In fourth gear 31" tires 60 mph 4.8 gears in axle would only push 3205 rpm.

 

[Tylerh84]

So what size tires ? I need this input since we know the tranny is .84 or so in 5th.

31x10.5 r15

My tach shows about 5> than what I'm actually going which leads me to believe the diffs have been re-geared. But either way the speedo should still show 60mph at 2500.

 

[Casey E]

Sorry didn't see the 31" tires post

 

[Tylerh84]

In fourth gear 31" tires 60 mph 4.8 gears in axle would only push 3205 rpm.

Ill take a video on my way home of all the shifts, tach, and speedo. I'll try to get 1st-5th in one video.

 

[Casey E]

To recreate what you are saying you would need an axle ration in the 7, nobody makes it, i.e. Won't fit, so you must have lower transfer case gears. I assume you mean 5 under speedometer?

 

[Tylerh84]

Makes me think somebody re-geared the transfer case but swapped the wrong gear. I have no idea at this point, it has to be something like that.

 

[Tylerh84]

To recreate what you are saying you would need an axle ration in the 7, nobody makes it, i.e. Won't fit, so you must have lower transfer case gears. I assume you mean 5 under speedometer?

Yes, it shows 5 over my actual speed.

 

[Casey E]

The motor would be screaming at 4K.

 

[Tylerh84]

The motor would be screaming at 4K.

Exactly, luckily I don't have to do too much highway driving but I'm always in the slow lane.

 

[Casey E]

Yep, sounds like transfer case gears and maybe axle gears. Ping Georg at Valley hybrids, he will figure it out instantly.

 

[Tylerh84]

To recreate what you are saying you would need an axle ration in the 7, nobody makes it, i.e. Won't fit, so you must have lower transfer case gears. I assume you mean 5 under speedometer?

any way I can identify if I have the factory transfer case? I'd like to order replacement gears.