300ci Transmission Selection Help

This applies to 300ci engines only

Frank

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I need experienced answers and advice (valid opinions too, please) about my tranny selection when I do the engine rebuild this winter. Fairly new to Ford, so I will be asking some elementary questions. My limited Ford experience is with C6 and E4OD only.
Vehicle: 1990 F150 Lariat with factory 300 and E4OD, both are original and tired @ 31 years and 200,000 miles.
( I will not be converting to a manual trans for a multitude of reasons, not the least of which is 20 years driving big rigs, and not modifying a good original condition Lariat. I know there is power loss in an automatic, etc but no need to discuss manual trans here, I will not be persuaded.)
The engine build will be a moderate upgrade from stock, and I do very little petal-to-the-metal driving, so a HP built tranny is not necessary. OD and locking TC are required.
Questions:
1) When considering getting away from electronic controls: Is the AOD a good tranny? (Meaning can it live behind 300 ft lbs and live for two decades). Does it have inherent weak spots?
2) Does the AOD match up to the big 6?
3) Is it the same length as the E4OD? I don't want to modify the drive shaft or do extensive mods to the crossmember. (Welding a modified bracket or such is ok.) Also must fit physically- no mods to firewall or cab floor. ?
4) Would the AOD output shaft match my current yoke?
5) I assume the AOD has electric controlled locking TC. ? ( I control the TC lockup with a toggle switch on the turn signal lever.)
6) Does the AOD have the feature of holding in second gear when the shifter is in 2, regardless of vehicle speed? This is crucial. Nothing irritates me more than easing along at 8 or 10 MPH with the vehicle lingering in 1st gear (campgrounds). If the AOD does not have this feature, we can stop right here.
7) Related to the question above- can the AOD be equipped with a "manual pack" valve body control?
:cool: Is the parasitic power loss of the AOD more or less than the E4OD?
9) Are there other compatible transmissions one would recommend? (This is not a hot rod build. Older man's daily driver in a sleepy southern town)

I am not opposed to staying with an E4OD. It is a robust unit, quiet and plenty strong behind a 6. I like it better than any of the GM or Mopar overdrive A.T.'s. But it's more expensive and I'm not a fan of wires running everywhere or computers of any kind. I would prefer hydraulic controls, but not a must. Thus the questions above. The following applies to both the E4OD and AOD:

I will be going to a 3.73, 3.90 or 4.10 rear gear, up from the (WAY too tall) factory 3.08. Stock original rims with P235/75 R15 Goodyear Wranglers. I already know the exact engine speed to road speed in every gear for all these ratios (has been posted on 3X5 cards taped to the dash for years) so my question here is not pros and cons of a particular rear gear ratio. Engine operating range will be 1600-3000. With the huge .71:1 or .67:1 (AOD) overdrive, there's plenty of vehicle speed with a low rear gear without exceeding the engine's sweet zone. My concern is correct speedometer calibration. This truck was just before electronic speedo.
10) Is there a correct speedometer gear available for either of these trannys in these rear ratios? If the AOD can work, it will definitely be a 4.10 rear, since it is geared higher across the board. I read that the drive worm is machined into the output shaft (E4OD) and I don't know if Ford makes a speedo gear that will work beyond the 3.73 ratio. (Remember, small tires.) I'm particular about my instruments, and I want the speedo reading correctly.
11) Is the speedo drive gear machined into the shaft on the AOD, or is there more flexibility in calibration than the E4OD?

I know I will get a flood of experienced information from y'all, and I thank you in advance. This project IS going to come to pass, but it will be a few more months before the physical work begins. . . I'm a planner. And getting all the $ together, of course! LOL
Soon I will start another post about the engine build. I have some questions there too, look forward to your feedback.
Thanks guys,
Frank
 

Frank

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Well, I see 44 views, and no replies. :rolleyes: I will be staying with the E4OD. I would appreciate advice on internal upgrades when it's overhauled. Thanks.
 

HitmanX

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Well I will reply...

The E4OD is a C6 back half with an OD up front. Ford did not reinvent the wheel in the 80s like all major auto makers with large transmissions AND there is NO way I would swap the AOD in place of the E4OD. A well built E4 is simple. Use a paper and rubber kit from a big player like Precision. I like Alto clutches, in autos I build for myself and customers I use high energy graphite (HEG) material. It is better than the old brown stuff and not that aggressive. It is just a modern material with modern adhesive to hold the material to the steel backing. Use a shift kit that is modest. I just put in two Superior PT4R100 kits this summer in AZ, easy. I can send the instructions if you want to see the involvement. Two pages are pump mods alone for volume and such. Shifts ideal, crisp and positive. Not harsh. Exactly as I wanted. Most start at most aggressive and regret it.

1. AOD is decent when built right. 4-3, 4-2, 4-1 downshifts are hell on the forward clutch pack as it reapplies under load, thus higher line pressure. It is a dynamic clutch, silly. The E4OD's forward is static in all forward gears. This is why AOD/4R70W/AODE have a high failure point in that clutch pack, plus it is tiny.

2. Same bolt pattern to attach.

3/4. AOD is shorter, so shaft will have to be elongated. Unsure on yolk spline count. Yes, being smaller fits where E4 does.

5. AOD has a mechanical lock up. Very odd, partially locked in third and fully in fourth. That is it unless you do a C6 input shaft swap and run a non lock converter.

6. Pattern is OD D 1. So you have to go up from 1 to D then back to 1 to hold second gear. Yes, really. The later AOD the better due to improved hydraulics and updated internals. E4OD has many updates to address also, but no biggie.

7. AOD is not electronically controlled if that is what you are asking. Just uses a throttle valve cable to the throttle body. Think 700-R4, 200-4R, etc.

8. AOD has one compound planet and much smaller, less power loss. No idea how much. Easy to move around by yourself, E4OD I recommend help.

9. You did not want a manual, I get it. I have three or four manual vehicles and they become tiresome after a while...so much so I just float gears often as my leg is tired. So, nothing really I can think of unless you went with a well built AOD which is easy.

To me, the 3.55:1 and 3.73:1 are so close, it is not worth the expense for the 3.73:1. You could swap the entire axle for cheap if you pulled it or grabbed a used gear set from the junkyard. Nearly all 4.6L 10th Gen vehicles have an 8.8" with a 3.55:1, my Expedition does yet is the 9.75" as a 5.4. 19 is the door tag, if yours is a pegleg, grab an H9 so you can toss in a limited slip 3.55:1 on the cheap. I am going to so I can junk my one tire fire 3.08:1...and I have 3.55:1 from Ford laying in the shop. Fiscally and timewise it just makes sense, toss in FMS carbon fiber clutches, reseal it, get on with my life!

10. Unsure on speedo, but I would think something is available.
 

Frank

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Thank you Hitman! I have never done AT teardown personally- because I never needed to. All the units in my past never needed touching. THM 350 and 400, Chrysler 727, Ford C6. China didn't exist when these rugged units were engineered. Between my son and me, two original 727's still going strong at 49 and 50 years old.
I will not be doing the rebuild on the E4 either- I don't have a proper shop, still work full time, (locally, the trucking days are past). and I don't want to spend time avoiding/ correcting rookie mistakes. Anymore, my time is more valuable than $.
I suppose this thread is silly. When I posted, was still leaning toward a non EFI engine build, and just wondered if the AOD was a good unit, being non-electric. What you answered is about what I expected, I really do appreciate the input. I am relatively new to Ford, so I asked. I like the E4. I can tell it's related to the C6. Tough, and quiet. Lots of AT's, I don't like their "tone".
No manual trans. I still like them for the control and efficiency, but I'm not cutting up this original condition truck, and as I said earlier, 20 years and 2.5 million miles of non-synchronized shifting wore all the fun out of it. I have the best of both worlds with a lock up TC, which I control manually with a toggle on the turn signal lever. And it is locked the moment I get over lug speed- no left leg required! :)

The E4 builds you mentioned is exactly what I am looking for. Firm, no-slip shifts without being harsh. The factory shifts are way too soft. I was told this was the ECU's fault. Will the Superior kit alone firm up the shifts, or will the ECM have to be modified? Yes I would like to read the instructions for the Superior kit.
I have no idea who to trust locally rebuilding the trans. The few shops I see look sketchy, with 20 cheap cars in the lot waiting their turn I guess. I want this done right, and done. I'll ask Gary at my machine shop, may have to take it to Savannah or Charleston. I have also looked online at buying rebuilt. Any recommendations on online trans purchase? But I like the idea of getting the parts you referenced, rebuild my unit, and I know what's in it.

The decision about rear gear ratio has produced much debate in my head. The snag is really the massive jump from 3rd to 4th, coupled with my mostly in-town driving conditions If I had another gear between 1:1 and .71:1, this would be simpler. the 3.08 is in the good power band (in 3rd) from 45-60 mph, (1700- 2300 rpm) but is lugging at 35, (1300 rpm) where I spend much of the time. 60 is the max speed limit I see. 3.55 brings me up to 1500 @35. That's ok, but then at 55 the 3.55 turns 2300 (3rd gear). I live in flat country, and don't need that much rpm. But OD @ 55 is only 1630 rpm, and that's a tad slow. Etc, etc. 3.73 is only 5% lower than 355, as you pointed out. 3.90:1 is really the gear that's the best in my slow speed world, but I don't know if there are any speedo gears for that or even for 4.10. Either of these gears enable me to operate in the power band from 30- 50, then use OD above that, without the low vacuum, bottom of the cam, can't pull an overpass highway rpm that I've been putting up with for way too long. 3.90:1 = 2.77 OD, 4.10 = 2.91. Still plenty tall. Gears and bearings are not expensive @ Summit racing.
 

HitmanX

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The only places I know that do E4OD and 4R100 are mostly Diesel specific from my pals on the 7.3 side. A trans build only takes me about a day, the valve body on some of my Euro cars takes a LONG time, but this thing has a fairly easy one so disassembly, cleaning, reassembly takes me about 3-4 hours now. Only done one E4OD and two 4R100 kits. Sadistic as it sounds, I like to build automatics.

The PT4R100 changes the firmness mechanically. You select it. The ECU will still think the transmission is all stock. The kit does a pile of pump modifications. That is how you up TCC lockup firmness, increase cooler flow, drainback, etc. Pump is most critical, but the firmness is flaccid at best stock. That is somewhat ECU related but mostly the accumulator springs chosen by Ford as well as the line pressure boost valve. BUT bear in mind this was done to satisfy the average customer. I hate crap shifts, I even put a shift kit in my Volvo V90 wagon I owned. That had an A341E.

You may just want to pop in the the valve body side of the shift kit and drive the trans until it fails or leaks so much it pisses you off. Then do pump mods later, we decided to do that on my pal's 4x4 Expedition. Pulling that did not appear fun. Period.

Mine being a manual has a shorter OD around 0.81:1 I recall, so a 3.55:1 with stock 235/75R15 does around 2300rpm at 70mph.

Valve body is easy. Drop pan...and all 20 bolts, 13mm head. Pull filter, if the all plastic one, reuse it. Filtran makes the OE filter for Ford if you have a cheaper plastic and steel unit. Clean the magnet. Start cracking fasteners loose. Mostly 8mm and a few 10s. Accumulator body up front will do nearly all of the increase in shift quality. You open up a few feed holes in the separator plate to fill the clutch packs faster and open the drain. Use Trans Gel or something to reinstall check balls, easy. E4OD replaces one spring in the actual valve body, I think has to do with line rise in low/reverse (at least 4R100 did). The rest I would disassemble, clean with brake clean, dry, lube reassemble. You will love how much better the thing shifts.

How large or small is the OE cooler on there?

Is the truck 4x4 or 2x4?
 

Frank

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Excellent info! Much obliged.
She's pretty tired. 198,000 miles of soft shifts, don't know how much life is left. It's only going to be a few months before the engine build, and I'm not leaving the old tranny in beyond that, regardless. So I probably won't mess with it before then. But I have the kit on the purchase list, and will use it when everything else gets done. (y)
Mine is a 2X4, all the room in the world down there. (love the old American trucks!)
I run an outboard cooler, not routed thru the radiator. A Hayden unit, 10"X10" in front of the AC condenser. No temp gauge, but have never had heat issues. (I have kept it serviced). It still shifts and locks up fine- just "soggy" between gears and slow going into R.
What is the issue with the metal filter vs the all plastic one? (I don't remember what's in it now).
 

HitmanX

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Supporter 2021
You are welcome for the info. Many other guys like that Transgo HD2 kit for the E4OD. TG kits tend to shift a hair firmer to me, but still do great things. Their AOD kit is the best around to me, it has all the ups and extras. I am 100% pleased with the PT4R100 kit, grabbed for $125 on ebay.

200k is a pile, the internal seals on the pistons are leaking for sure. Just how it is. Bet you many clutches are still pretty solid. Some 35-40 year old transmissions I have torn down have comically hard o-rings. One I was able to shape into a letter.

Honestly, I bet just good clutches and steels would be sufficient on a quality job with the aforementioned valve body upgrades. I would do the later steel planets while all down, but that is me.

EDIT - forgot about filter. The metal and plastic seem thinner and cheaper in my hand than the Filtran unit, it is just large. I just use cheap fluid, DexIII/Mercon from Walmart. You could do Mercon V if you want, it is apparently a syn fluid sort of like Dex VI and both can go in place of the other.
 
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BigBlue94

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I bought a 94 bronco with 351w and E4OD in 2003. Had a slightly deeper B&M pan and a shift kit of some sort. Shifts were firm but not harsh. A cracked head lead to a 340hp, 475ft/lbs rebuild of the windsor (limited to 260hp and xxx torque by factory injectors). The e4od took it like a champ regardless. Ill add I was 18-20 years old at the time, and it had 4.88 gears and 37" tires.

Hitman seems to have covered way more than i could ever add. I would've told you to drop a 5 speed and clutch in it.

If you want to keep the E4od torque converter locked, for towing purposes, there is an easy mod using a toggle switch. It does not interfere with eec control when switched off.
 

Frank

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Yes, thanks BigBlue. I operate the lock up manually, same ground wire mod you posted earlier, somewhere. Only difference, I cut it from the ECM, so mine is 100% manual control. I like when the engine is bound to the tires thru a clutch. Manual trans are more efficient, and a better feel when throttling, and much better decel than going thru a slipping TC, no doubt. However, this build will stay with the E4. Really, I feel like I have the best of both worlds with an auto and locking TC. I lock it as soon as second gear is above lug speed, and it stays locked till the next full stop. I have left hip and lower back issues from damage caused by 20 years driving simi's. Every one I ever drove, the clutches were very stiff, perhaps 50-80 pounds of force to depress. It made NO sense, I never understood why they weren't engineered with power assist hydraulic clutches, there was a D plenty of power available to power that small load. I spent many hours behind the wheel back then designing one in my head, would not have been a hard mod, there was plenty of room, engine accessory drives, etc. But at the time I was keeping a family of 4 provided for and when I was home, I was playing with kids, not thinking about optional truck mods.

One more thing I agree with you on but have never posted on those threads: Low rear gears are the way to go! With all the tranny's being OD, there is no reason to give away take off/ pulling torque that is 100% free, since at high speed the OD keeps the engine sane. This F 150 rebuild will include 3.90 or 4.10 gears. I have a 1989 F250 4X4 original 7.3 NA diesel, 5 speed, stock 16.5 wheels and 4.56 rears. That mule would pull the house down in granny without touching the gas. Low rears: (y)

Early in my trucking career, I discovered a then hidden advantage to low (numerically high) diff gears, and it surprised the whole industry, but was proved true and led to changes in industry standards. . . (I'm trying to think how to post this without it being a mile long...)
When I first started my career in 1988, I was a company driver. Most company trucks back then had a 350HP Cummins (855 cu in L6) with a 9 speed direct-drive tranny and 2.75-2.90 rears. These engines govern out at 1950 RPM, +/- . So the truck was automatically governed to 65 MPH +/- by being "gear bound". At 65 in HI gear, the engine rpm hit the mechanical governor limit, and that's all ya got. About that time, simi's first began coming out w/ OD, and lower rear ratios. I worked out of Charlotte, NC, then later Greensboro, NC. I spent a high % of time crossing the Appalachian mountains. My first experience with OD was an '88 Freightliner Cab Over with a 310 HP Cat (a small injector, small turbo 3406, 893 cu in L6. 1500 ft lbs @ 1200 RPM), 9 speed OD and 4.10 rear. It was still gear bound @ 65, the single OD gear bringing the final drive ratio back to +/-2.90. What I discovered was this: Two vehicles with the same power and same weight pulling a mountain grade, the one with the lower rear gears would slightly outpull the one with taller rear gears including when the final drive ratios were the same. In other words: two 80,000 pound trucks are side by side, loosing speed as they pull a long 10% grade. One has 2.90 rear and 1:1 tranny, the other 4.10 rear, OD tranny. Both trucks are turning 1600 RPM @ 100% fuel with the tranny being geared down more in the 2.90 truck than the 4.10 truck, but the final drive ratio is the same. The truck with the lower (numerically higher) rear end will hold speed longer, while the taller geared vehicle would continue to gradually loose speed, and have to drop more gears. The industry quickly discovered this too: lower rears "held on" to power to the wheels longer when the load was exceeding the power output and pulling the speed down, even when the transmissions were geared so that by the math, both engines were seeing the same rotational reduction. On paper the wheel pulling force was the same. In real life, the low rear truck was first to top the summit, and produced better fuel economy. The theories abounded in trucking magazines as to why. Reduced drive line load was about all they could come up with. None of the theories were fully satisfactory to my mind, but the difference was real. I ended up buying that '88 truck, my first of six over the years- she was a strong pullin' ox with those 4.10 rear ends. From that lesson, all my trucks after that first one had 4.10-4.31 rears and double or triple OD 12-18 speed tranny. By 1990, all big trucks came from the factory with lower rears and OD trans.
 

Frank

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Hitman, responding from the other thread- I may look for a used set (rear gear). I have firmly decided to go to 4.10's when I do the rebuild. We talked about this above, last month. I could get 2 for one if I could find a whole 8.8 axle with the 4.10. My 79 F100 has an 8" with 2.80 gears (and pinion bearing noise). Terrible ratio with the 3 on the tree and in-town driving. Would put the 3.08 rear that's in the 90 in the 79, and the new 4.10 in the 90. It's been decades since I hit a salvage yard. there's not much around here, but 'couple of big ones an hour or so away. Need to get on the phone and track one down.
Yes the Trutrac will be part of the investment. Appreciate everyone's input. You say FMS or Yukon gears? For a 225 HP application, is there that much difference? Richmond gear And Ford Performance have 4.10's at Summit for under $200.
 

bubba22349

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Wow Frank, so somebody changed out the excellent stock 9 inch axle of your 1979 F100 for the smaller 8 inch axle? That's a real shame as those stock axle would also of had the big 31 spline axles they are pretty tough units and easy to change out the Ring and Pinon's in them theres a very large selection of gear ratio choices for them too. Good luck
 

Frank

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Wow Frank, so somebody changed out the excellent stock 9 inch axle of your 1979 F100 for the smaller 8 inch axle? That's a real shame as those stock axle would also of had the big 31 spline axles they are pretty tough units and easy to change out the Ring and Pinon's in them theres a very large selection of gear ratio choices for them too. Good luck
Good morning bubba. Yes, unfortunately there's a baby axle under her. One originally behind an auto trans, no doubt. The PO didn't know the truck's history, and was not a mechanic or vintage enthusiast. We purchased it to help the PO, was having health issue and needed $, I had my eye on a '66 in Charlotte. But "God's ways are not our ways." I wish it still had the 9 inch! Between that and other pesky irritations, we are preparing to sell this truck. I've poured $ and labor into the front end, engine, etc, but it still just isn't "fitting in with the family", you know what I mean. Wife doesn't like it, so will be posting it for sale very soon, will use the $ to finance overhaul of the '90.
 

HitmanX

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Very interesting to me the nearly same top gear ratios achieve the same economy. All I would think of is mechanical advantage. Whenever I have regeared vehicles economy in the city goes up due to the advantage. Highway may drop some, but the difference there is minor at best.

On your E4OD truck with the 3.08:1, if on a stock 235/75R15 and the 0.72:1 OD of the E4OD, it shows about 1800rpm with stock gear at 70mph. With a 4.10:1 is a modest 2400rpm, which to me is right on top of the power to cruise at that speed with a 4.9. I am sure you know the faster you go the more power is needed. Easily overlooked basic physics by folks. My '92 with an M5OD and a 3.55:1 would do about 2300rpm in top gear, now it has a pegleg 3.08:1...those gears are going in my pal's 2.3L turbo Thunderbird and the 3.55:1 set is from my '88 when I popped in a 4.10:1 set almost 20 years back!

For that '79, I would consider an entire 8.8" swap as it easily sounds in your realm. PLENTY of 3.55:1 equipped 8.8" axles in the yards. All the 87-96 302/auto trucks pretty much had this ratio. The 97+ with 4.6 also had the 8.8.

FMS or I guess they are Ford Performance now gears fit perfect, but I understand from my pal that runs an offroad shoppe the Yukons fit excellent in the axles he does. I have no experience with Richmonds, but they have been around forever so must be good quality.
 

Frank

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1) you say city economy goes up with the lower rear, and that's a closer scenario to an engine at full power in a bind and loosing speed that I described above. It's rare for a 4 wheel vehicle to ever be in that situation, so it's not something anyone would consider. But when full power is applied and the vehicle is only maintaining or loosing inertia, lower rears get more power to the ground regardless of transmission ratio. the difference is significant, even though the math won't show it.
2) The final drive ratio with .71 OD @ 3.08:1= a pathetic 2.186:1. .71OD@ 4.10:1=2.91:1 final ratio, and that's much better. My stock 4.9 can't pull any hill at all in OD, and cruises at 60 in OD with only 8-10" manifold vacuum. I can't stand it, it's just lugging. Factory tach reads 1900@ 70 now. My calculations based on a linear multiple of actual tach readings now show 2529 rpm @ 70 w/ 4.10's. That's a tad high for my personal preference as a cruise speed, but I've decided on 4.10 because I very rarely drive that fast. Actually- never. 60-65 is my highest cruise speed. 60-65 mph= 2125-2300 rpm- that's the perfect sweet spot for an L6 with a 4" stroke. 55mph=2000. To each his own, but for me this is ideal, and the engine rebuild components will match this target. Need to pass? 3rd gear at 55 = 2800. Nice. And not to mention the 33.1% torque increase everywhere. Man, I'm ready to get this build going. .
3) the physics of speed are not comprehended by drivers, and we've all seen the accidents to prove it. Inertia = 1/2 the mass squared.
Doing the math reveals the power requirements- and increased stopping distance- as speed increases. For example, take a base speed of 49mph. 55= 23% more inertia. 60= 47% more. 65mph=72% more. At 70 mph inertia, wind resistance and stopping distance (and impact injury) is double the inertia at 49 mph. So the sum total engine power it took to go from 0 to 49, it takes all that again to go from 49 to 70, plus the doubled wind resistance. I'll be in the right lane at 62, everyone else can go around.
4) Think I'm going with the Ford Performance gear set. Ford gears in a Ford rear- seems logical. Stock duty will be ample with my driving habits and modest power.
 

bubba22349

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I could give you what my truck did for a comparison it was a 1994 an F150 short bed 4.9 a 5 speed (M5OD) a 3.08 rear axle and the stock size tires if you want but sounds like you have it set right now.
 

Frank

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I could give you what my truck did for a comparison it was a 1994 an F150 short bed 4.9 a 5 speed (M5OD) a 3.08 rear axle and the stock size tires if you want but sounds like you have it set right now.
Yes, Bubba. I would be interested to see those numbers with the 5 speed. Thanks
 
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