4.0 clutch and flywheel upgrade for 2.8 Rangers discussion.

[bbbc3]

Here is my experience with the 4.0 clutch and flywheel upgrade…

I recently swapped my 4spd manual for an M5OD on my 2.8l engine. I considered this to be a good time to also upgrade the clutch and flywheel with the popular 4.0 clutch upgrade.

Results: Now that I have the new flywheel and clutch in the truck it is not performing well on the highway! I can not even use 5th gear and even in 4th gear, the truck can not pull hills. It is embarrassing on the hwy. I can hardly hold 65mph. Before with the 4spd and 2.8 clutch/flywheel I could go any speed I wanted an even pull passed cars in the passing lane if needed. Not anymore! I can only associate this to the larger and MUCH heavier flywheel!

Anyone else have the same experience? Or can anyone confirm that my lack of performance on the hwy is actually related to the larger flywheel? I'm thinking my only option is to pull the transmission again and put the stock 2.8 clutch and flywheel back on the truck.

Also, I’d like to make sure that the later model slave cylinder and throw out bearing that I just upgraded to will work on the stock 2.8 flywheel and clutch.

 

[bbbc3]

Anyone, please let me know if my experience above seems normal or if there could be another issue going on?

 

[wildbill23c]

Here is my experience with the 4.0 clutch and flywheel upgrade…

I recently swapped my 4spd manual for an M5OD on my 2.8l engine. I considered this to be a good time to also upgrade the clutch and flywheel with the popular 4.0 clutch upgrade.

Results: Now that I have the new flywheel and clutch in the truck it is not performing well on the highway! I can not even use 5th gear and even in 4th gear, the truck can not pull hills. It is embarrassing on the hwy. I can hardly hold 65mph. Before with the 4spd and 2.8 clutch/flywheel I could go any speed I wanted an even pull passed cars in the passing lane if needed. Not anymore! I can only associate this to the larger and MUCH heavier flywheel!

Anyone else have the same experience? Or can anyone confirm that my lack of performance on the hwy is actually related to the larger flywheel? I'm thinking my only option is to pull the transmission again and put the stock 2.8 clutch and flywheel back on the truck.

Also, I’d like to make sure that the later model slave cylinder and throw out bearing that I just upgraded to will work on the stock 2.8 flywheel and clutch.

Check the gear ratios in your 4 speed VS the 5 speed, bet your speed loss is in there somewhere. That flywheel isn't that heavy to cause you to lose that much power LOL. Something else isn't right and a 4 speed and 5 speed manual were both optional back then in the Ranger, but different gear ratios.

A friend of mine has a similar issues but in a 94 F250 7.3L IDI due to changing a transmission out that was failing, his truck now just doesn't have the same get up and go because the pulled a different transmission which had different gear ratios in it.

 

[bbbc3]

I bet you’re right.
This little article says that the heavier flywheel should be an improvement.

Can A Heavier Flywheel Make Your Jeep Easier To Drive? - FOUR WHEELER NETWORK

Many of us think of weight as the enemy, whether it’s our beltline or our Jeeps. Weight places additional stress on all kinds of Jeep parts from the suspension

www.fourwheeler.com

I maybe dropping in 4.10 gears soon.

 

[PetroleumJunkie412]

Dead on with the trans gearing bill. What was the M5OD pulled from?

Gear ratios in them internally vary. I got lucky in my donor - Was a rare 2.9 M5OD truck.

Depending on the ratio of your rear end, dropping a ratio or two may be necessary.

Has your 2.8 been duraspark converted?

 

[don4331]

bbbc3:

Do you know what ratio you are currently running in your differentials?

With your 32" tires, the OD of the M5OD is probably putting your revs below the power band. The advantage of the overdrive is it makes 4.56s feel like 3.55s on the freeway.​

 

[bbbc3]

I am currently running 3.73 gears.

 

[bbbc3]

My M5OD came from a 2.9 as well. I have not durasparked my truck. I’m seriously considering the Holley sniper 2bbl efi.

 

[8thTon]

Now that I have the new flywheel and clutch in the truck it is not performing well on the highway! I can not even use 5th gear and even in 4th gear, the truck can not pull hills.

Is 4th gear different that it was before? Is 4th in both transmissions 1:1?

Flywheel mass cannot really have any effect accept in rapid engine acceleration. It is just storing a bit of energy when the engine is accelerating, which is then available to be released when something tries to slow the engine down.

Is the clutch slipping?

 

[bbbc3]

Is 4th gear different that it was before? Is 4th in both transmissions 1:1?

Flywheel mass cannot really have any effect accept in rapid engine acceleration. It is just storing a bit of energy when the engine is accelerating, which is then available to be released when something tries to slow the engine down.

Is the clutch slipping?

I’m really not sure how to tell what my trans ratios are.
The clutch isn’t slipping.

 

[8thTon]

I’m really not sure how to tell what my trans ratios are.
The clutch isn’t slipping.

4th gear in many manuals is a special case, in that there really isn't a gear at all and the input an output shafts are just locked together. In many newer gearboxes that isn't the case, and so 4th can have a ratio other than 1:1. It's really a general architecture question that someone familiar with these transmissions can answer.

 

[bbbc3]

bbbc3:

Do you know what ratio you are currently running in your differentials?

With your 32" tires, the OD of the M5OD is probably putting your revs below the power band. The advantage of the overdrive is it makes 4.56s feel like 3.55s on the freeway.​

Would you recommend 4:56s?

 

[don4331]

I went with 4.10s with when I still just had the 4.0 (ohv) as 3.73s, weren't cutting it when I was towing; I would have went deeper but 4.56s are unicorns in recyclers locally. My tires are 31x10.5R15s; but I have plans for 33s.

4.56s *.812 (OD) in 5th = 3.70; so just a little higher than the 3.73s you have. So, it would make the truck more/less same as it was with the 4 spd.

Old 4spd - 1st 3.96; 2nd 2.07; 3rd 1.39; 4th 1.00; Reverse ?
M5OD 1st 3.77; 2nd 2.21; 3rd 1.52; 4th 1.00; 5th .81; Reverse 3.40

You need to decide if you would like lower rpms on freeway; or lower gears off road as a result of your transmission swap.

 

[sgtsandman]

If you are going to spend money on re-gearing, I would just go straight to 4.56 if you are going to be running 32" tires. I'm running 31" with 3.73, which is ok but for towing and trails, 4.56 would be better and still able to do highway speeds.

 

[bbbc3]

Thanks guys for your input! I ordered 4.56 gears today. I wish I could change the name of this thread but maybe it will let others know The effects of gearing on the M5OD.