3.73 to 4.30 conversion question
#31
Ok for those of you wanting to do this on your own. I'm just getting ready to finally install mine and found some problems. All the aftermarket is going to sell you a standard dana 60 gear set. While this will fit in the super 60 it's not the way I wanted to go being the super 60 has a bigger 10 inch ring gear vs. 9.75 on a normal 60. So I ordered the front gears front the dealer for not much more than the aftermarket. Open the box and its a full kit down to the last bolt. I'm going to ask if the rear comes a full kit as well. If so, the aftermarket is screwing us all. My yukons are reboxed ford gears and the price is nearly the same. But Ford sell them as a kit for the same price as the yukons the aftermarket seems to be pocketing the kit and selling it as well. Just some fyi
#32
Yes, it is a full kit.
Rear: Part number BC3Z42095 = $509.57
Front: Part number DC3Z3222C = $373.94
Gasket: Part number TA29 =$47.58
Then the fluids. I was warned about attempting to do it myself by an independent mechanic with 40+ yrs experience that parts alignment was critical and needed to be done with computer or there would be issues. I dunno, but took his advice. Have fun daily because one day won't be fun.
Rear: Part number BC3Z42095 = $509.57
Front: Part number DC3Z3222C = $373.94
Gasket: Part number TA29 =$47.58
Then the fluids. I was warned about attempting to do it myself by an independent mechanic with 40+ yrs experience that parts alignment was critical and needed to be done with computer or there would be issues. I dunno, but took his advice. Have fun daily because one day won't be fun.
#33
Yeah it's kind of amazing the dealer is the place to go for these, first time ever for me. I'm sure the factory has a fancy way to install and check gears now days, but your dealer most likely did it the same way it's always been done. There is a little bit of skill that comes from experience as do doing gear sets but it's not really as hard as it's made out to be. The right tools help a lot and make it easier. I like this truck because I am able to still work on it vs. a lot of the new vehicles. For example my wife's new escape, I'm not a fan of working on it.
#34
I know exactly what you're saying. This is my first Ford since 1979 so I am not as aware what FoMo does as I would like. I've worked on all my GM's with little trouble - even the LB7 diesel, which broke me of being enthused about working on vehicles (plus my body revolts now when I think of getting out the wrenches). I've never been a tranny monk; so didn't figure now was the time to get experience.
Having the right tools for the job is a must these days. Every time I turned around there was a new/improved tool for the LB7 engine. Not like the old days when a pair of pliers and some bailing wire worked !
Having the right tools for the job is a must these days. Every time I turned around there was a new/improved tool for the LB7 engine. Not like the old days when a pair of pliers and some bailing wire worked !
#35
NOT performing a proper break in on new differential gears goes directly against the advice of every single experienced gear guy I know. They ALL advise to spend the first 500 miles or so breaking them in via heat cycles. If you're going to spend the change to have gears swapped, it would surely suck to ruin them because they weren't broken in. Especially for heavy towing situations. I'm not a gear swap expert myself, but maybe others on here will chime in to corroborate (or contradict) this.
#37
truckfella - - I'm from the "old school" .... "very old school", and I agree with your statement 100%. That's why I have not pulled with the new gears in the truck yet. I've got another 75 miles before hitting 500 - then I will pull. I'm still debating with myself on whether to change gear oil before pulling. Yeah - I know FoMoCo says it doesn't need changed for 100k miles (or something like that), but "old school" says there will be metal in the mix after initial break-in/mating.
#38
Rubicon and ATP - I made my first pull with the 4.30 gears today. It was a short pull of 85 miles round trip in SE Missouri where the hills are made by moles and the air is thick enough to make molasses seem thin. Well - ok - maybe not quite, but you get the picture.
The pull under these conditions left me yawning and admittedly a bit disappointed. For the most part I locked out 6th gear, but when I did allow it to engage the truck wanted to gain speed easily up to 70mph. I do not tow faster than 65mph deliberately. (Tires are main consideration)
At 55mph (County Rds) the engine turned 2000 rpms in 5th gear and at 65mph on I-55 the engine turned 2500 rpms. It seemed a bit sluggish getting to 60mph and giving more pedal had little affect in terms of reaching cruise speed quicker. I did punch it trying to enter I-55 ahead of traffic and was rewarded with the ole' 2nd gear rev at 6000rpms going nowhere slow; only to have to let traffic go by and try again. This event took place with "Tow Haul" mode engaged.
I ended the 85 mile trip with a lie-o-meter reading of 8.0mpg. Conditions today were 81 deg F and W-to-E wind of about 20mph. (My travel was N-to-S and back)
My plans are to head to Montauk, MO next week which will put me in significant Ozark Mountains and I can get a better idea of the performance hopefully. At this point I would say - don't rush to change the 3.73's to 4.30's. Just my first pull though.
Rich
The pull under these conditions left me yawning and admittedly a bit disappointed. For the most part I locked out 6th gear, but when I did allow it to engage the truck wanted to gain speed easily up to 70mph. I do not tow faster than 65mph deliberately. (Tires are main consideration)
At 55mph (County Rds) the engine turned 2000 rpms in 5th gear and at 65mph on I-55 the engine turned 2500 rpms. It seemed a bit sluggish getting to 60mph and giving more pedal had little affect in terms of reaching cruise speed quicker. I did punch it trying to enter I-55 ahead of traffic and was rewarded with the ole' 2nd gear rev at 6000rpms going nowhere slow; only to have to let traffic go by and try again. This event took place with "Tow Haul" mode engaged.
I ended the 85 mile trip with a lie-o-meter reading of 8.0mpg. Conditions today were 81 deg F and W-to-E wind of about 20mph. (My travel was N-to-S and back)
My plans are to head to Montauk, MO next week which will put me in significant Ozark Mountains and I can get a better idea of the performance hopefully. At this point I would say - don't rush to change the 3.73's to 4.30's. Just my first pull though.
Rich
#39
Rubicon and ATP - I made my first pull with the 4.30 gears today. It was a short pull of 85 miles round trip in SE Missouri where the hills are made by moles and the air is thick enough to make molasses seem thin. Well - ok - maybe not quite, but you get the picture.
The pull under these conditions left me yawning and admittedly a bit disappointed. For the most part I locked out 6th gear, but when I did allow it to engage the truck wanted to gain speed easily up to 70mph. I do not tow faster than 65mph deliberately. (Tires are main consideration)
At 55mph (County Rds) the engine turned 2000 rpms in 5th gear and at 65mph on I-55 the engine turned 2500 rpms. It seemed a bit sluggish getting to 60mph and giving more pedal had little affect in terms of reaching cruise speed quicker. I did punch it trying to enter I-55 ahead of traffic and was rewarded with the ole' 2nd gear rev at 6000rpms going nowhere slow; only to have to let traffic go by and try again. This event took place with "Tow Haul" mode engaged.
I ended the 85 mile trip with a lie-o-meter reading of 8.0mpg. Conditions today were 81 deg F and W-to-E wind of about 20mph. (My travel was N-to-S and back)
My plans are to head to Montauk, MO next week which will put me in significant Ozark Mountains and I can get a better idea of the performance hopefully. At this point I would say - don't rush to change the 3.73's to 4.30's. Just my first pull though.
Rich
The pull under these conditions left me yawning and admittedly a bit disappointed. For the most part I locked out 6th gear, but when I did allow it to engage the truck wanted to gain speed easily up to 70mph. I do not tow faster than 65mph deliberately. (Tires are main consideration)
At 55mph (County Rds) the engine turned 2000 rpms in 5th gear and at 65mph on I-55 the engine turned 2500 rpms. It seemed a bit sluggish getting to 60mph and giving more pedal had little affect in terms of reaching cruise speed quicker. I did punch it trying to enter I-55 ahead of traffic and was rewarded with the ole' 2nd gear rev at 6000rpms going nowhere slow; only to have to let traffic go by and try again. This event took place with "Tow Haul" mode engaged.
I ended the 85 mile trip with a lie-o-meter reading of 8.0mpg. Conditions today were 81 deg F and W-to-E wind of about 20mph. (My travel was N-to-S and back)
My plans are to head to Montauk, MO next week which will put me in significant Ozark Mountains and I can get a better idea of the performance hopefully. At this point I would say - don't rush to change the 3.73's to 4.30's. Just my first pull though.
Rich
#42
would be interested to see if that helped more than the $2k in gearing.....certainly the gearing can't hurt when pulling heavy, but I also wonder if this DBW crap is the cause of dissatisfaction more than gearing.
I remember when trying to decide between Ram 6.4 with 4.10's vs 6.2 4.30's I remember seeing a final gearing chart that put the 6.2/3.73 combo very close to the Ram 6.4/4.10 combo due to lower internal transmission gearing in the ford. So it is very surprising to me that two trucks with similar final gearing and similar hp\tq motors can feel so different.
I don't want to hijack the thread with the DBW stuff....but it's got me wondering...
#43
#44
I've started a new thread on DBW in the interest of keeping this topic on 4.30 gearing conversion.
https://www.ford-trucks.com/forums/1...l#post15234130
https://www.ford-trucks.com/forums/1...l#post15234130
#45
Super Dan - Keep us informed on the performance after you do the 5* tune.
At present I am not wanting to pursue after-mkt tuning systems. I've gone down that road before with diesel and yeah - it was "fun", the truck would burn rubber in 3 gears, it would make tons of smoke, and it would jump from 70mph to 100mph in nothing flat. At the end of the day I spent a lot of money, got less mpg, and still didn't pull heavy loads faster than 65mph.
Now for the saddest part - '03 Bowtie 2500HD w/LB7 Dmax, Tuner set, pulling heavy; going up hill at 50mph best and I get passed by a Dodge Ram pulling heavier. No one could make the LB7 perform better. Needless to say I was not pleased.
In short - I have slowed down in my old age, but I'm not ready to crawl again. Pulling slower is ok as long as it's not impeding traffic.
At present I am not wanting to pursue after-mkt tuning systems. I've gone down that road before with diesel and yeah - it was "fun", the truck would burn rubber in 3 gears, it would make tons of smoke, and it would jump from 70mph to 100mph in nothing flat. At the end of the day I spent a lot of money, got less mpg, and still didn't pull heavy loads faster than 65mph.
Now for the saddest part - '03 Bowtie 2500HD w/LB7 Dmax, Tuner set, pulling heavy; going up hill at 50mph best and I get passed by a Dodge Ram pulling heavier. No one could make the LB7 perform better. Needless to say I was not pleased.
In short - I have slowed down in my old age, but I'm not ready to crawl again. Pulling slower is ok as long as it's not impeding traffic.