There is transmission confusion, I can't get no relief.

[frankendat]

There may very well be too much information on the Internet, as I have twisted myself and trusting the Ratsun brain trust more than most, ask for clarification.

From searching and reading here, the following are thought to be true:

1.      A 1984 720 4x4 (gas) 2.4l came with a FS5W71B transmission. (aka Shorty or Stumpy)

2.      The FS5W71B transmission is not as robust as a FS5W71C transmission

3.      Modifications necessary to employ a FS5W71C transmission include a lifting spacer, shifter modification, and custom driveshaft (if utilizing a 71C from an S13—Madkaw. Uncertain if custom driveshaft is necessary if utilizing a 71C from a 1988 2wd Hardbody---Bottomwatcher).

4.      Based on commentary on the two 71C transmission swaps, if a custom driveshaft can be avoided with the Hardbody transmission it is the less expensive option.

 

According to the website of Midwest Transmissions, the transmission used in a 1988 2wd Hardbody is a FS5W71E. However, Midwest Transmission lists the FS5W71C for a 2000-2004 2wd Frontier. (But, I believe, the bellhousing on the Frontier would not be compatible.)

I sent an inquiry to Midwest Transmission with information above and asked them to clarify. We’ll see. I will post if there is reply.

 

Roadkillcustoms, lists L4N71B as the transmission for a 86-89 Nissan w/2.4L and RL4R01A as the transmission for a 90-98 Nissan w/2.4L. (I include the Roadkillcustoms info, because if it has any legitimacy, they have done much leg work in determining what parts from what vehicles interchange and I have found savings using that method, most recently with a bearing for my transfer case. (I have also wasted money with that method))

 

I have a couple 71B’s and a rebuild kit and the more I go over the information the more I realize how much I don’t know about transmissions and how aggravated I will be if I rebuild a 71B and it fails, before a decade.

[datzenmike]

1/ probably a 26" shorty but 720s also had the long 31.5". 

 

2/ yes

 

3/ the 71C are around 35" or 30" long but if replacing a 71B you definitely will need to modify the driveshaft length. Shifter location may not fit the hole in the floor but shifter does not need any modifications and as far as I know do not need a lifting spacer.

 

4/ see 3/

 

The Z series engines use the same bolt and position pattern as all KA series engines so a KA24E or KA24DE 71C transmission will bolt to and fit the 720 Z series engines.

 

The L4N71B and the RL4R01A are true 4 speed over drive automatics.

 

L4N71B (RWD)

'81-'84 Maxima L series

'82 S110 200sx L series

S12 200sx CA engine

D21 Hardbody till '89 then RL4RO1A

GC22 Vanette Z series engine also used the RL4RO1A the last year.

Z31 300zx VG engine '84-'89

 

RL4RO1A (RWD)

'89 S13 240sx

'90- Hardbody

'90- Z32 300ZX

 

 

 

 

 

[bottomwatcher]

My C came from an 88 hardbody 2wd. Says C on it. I did have to have the primary shaft lengthened? It was 18 years ago but at the time $100. Stoffregen says $200 ish now.

Ok spacer confusion. The rear C mount will not reach the original crossmember so a simple adapter will have to be made. I used 1/2" steel plate about 4" long with 4 holes. You are simply bolting the plate on top of the crossmember creating a landing spot for the rear mount to be bolted to. Since this now places the rear of the trans 1/2" higher than stock I dropped the height of the crossmember using 1/2" spacers between the crossmember and frame creating a net height change at rear of transmission at zero. Maybe not necessarily but I don't like to change drive angles if there is an easy solution to negate it. Change one little thing and it is amazing what kind of shitstorm you can brew downstream.

[datzenmike]

The first FS5W71C was in the new '84 300zx non turbo. All other 71Cs replaced the 71B in half way through the '86 model year in the S12 200sx and at the end of the 720 and start of the D21.

[frankendat]

22 hours ago, frankendat said:

According to the website of Midwest Transmissions, the transmission used in a 1988 2wd Hardbody is a FS5W71E. However, Midwest Transmission lists the FS5W71C for a 2000-2004 2wd Frontier. (But, I believe, the bellhousing on the Frontier would not be compatible.)

I sent an inquiry to Midwest Transmission with information above and asked them to clarify. We’ll see. I will post if there is reply.

 

Midwest  Transmission replied (and promptly no less) They did not address the FS5W71E, but did confirm the information confirmed by Ratsun. The relevant portions of the Midwest Transmission reply are pasted below.

"The main difference between the transmissions from the 720 to the D21 Hardbody (1986.5-up) is the shifter design.

Unfortunately, on the FS5W71 transmissions they are getting hard to find and we require the customers unit be sent in to be built, I don’t have any available."

[frankendat]

10 hours ago, bottomwatcher said:

My C came from an 88 hardbody 2wd. Says C on it. I did have to have the primary shaft lengthened? It was 18 years ago but at the time $100. Stoffregen says $200 ish now.

Ok spacer confusion. The rear C mount will not reach the original crossmember so a simple adapter will have to be made. I used 1/2" steel plate about 4" long with 4 holes. You are simply bolting the plate on top of the crossmember creating a landing spot for the rear mount to be bolted to. Since this now places the rear of the trans 1/2" higher than stock I dropped the height of the crossmember using 1/2" spacers between the crossmember and frame creating a net height change at rear of transmission at zero. Maybe not necessarily but I don't like to change drive angles if there is an easy solution to negate it. Change one little thing and it is amazing what kind of shitstorm you can brew downstream.

18 years with a transmission would be fantastic and appropriate, in my mind, as days of banging gears and cooking rubber are long past. Keeping alignment, as precise as possible, I too, believe prudent. 

[frankendat]

18 hours ago, datzenmike said:

The L4N71B and the RL4R01A are true 4 speed over drive automatics.

Automatics! I didn't even consider that--Duho

[bottomwatcher]

Yep. I sent 4 b series to the scrapyard. I wasn't hard on them just a lifted truck with biggers tires puts a real load on the countershaft. C series are actually fairly plentiful because they used them up until the early 2000s it think from hardbodies to frontiers on the Kae and de series. You want the 2wd version because of the divorced transfer case of the 720.

[frankendat]

31 minutes ago, bottomwatcher said:

Yep. I sent 4 b series to the scrapyard. I wasn't hard on them just a lifted truck with biggers tires puts a real load on the countershaft. C series are actually fairly plentiful because they used them up until the early 2000s it think from hardbodies to frontiers on the Kae and de series. You want the 2wd version because of the divorced transfer case of the 720.

It is my plan to lift a little. I want to run 235/85R16 (Toyota rims) should be about 32" OD, might require a 1" or 2" lift. As for the transmissions being plentiful, I put that claim to the test. If it works out, I'll PM the details.

[datzenmike]

There were 3N71B automatics all through the '70s and around '81 a locking torque converter was added to make them more efficient on the highway. These were called an L3N71B but I don't think the L was for locking as later again there were E3N71B used on the Z22 powered S110 200sx. This is true of the L4N71B where there were E4N71Bs for the VG powered S12 and turbo 300zx. So L is possibly for Light duty and E is heavy (er) duty?  

 

 

[frankendat]

Adding to my earlier response, I forgot to mention the 7.50X16 and/or the 8.25X16. Those sizes are more prolific in Canada, maybe one of our Canadians can weigh in on successful  use of those tire sizes in the Great White North?

[frankendat]

Update on the transmission:

Midwest responded to my cost estimate request: cost of transmission rebuild, I supply 71C core and pay freight--my core to Midwest and rebuilt back to me. In other words, price not including shipping = $1026.00

Everything is getting expensive, but DAMN

[frankendat]

13 minutes ago, frankendat said:

Adding to my earlier response, I forgot to mention the 7.50X16 and/or the 8.25X16. Those sizes are more prolific in Canada, maybe one of our Canadians can weigh in on successful  use of those tire sizes in the Great White North?

 

23 hours ago, datzenmike said:

There were 3N71B automatics all through the '70s and around '81 a locking torque converter was added to make them more efficient on the highway. These were called an L3N71B but I don't think the L was for locking as later again there were E3N71B used on the Z22 powered S110 200sx. This is true of the L4N71B where there were E4N71Bs for the VG powered S12 and turbo 300zx. So L is possibly for Light duty and E is heavy (er) duty?  

 

 

 

[bottomwatcher]

31x10.5s rub slightly with a 2" upper A arm lift, 2 inch body lift and some fender trimming. Going to need more for 32s.

[MikeRL411]

On 1/5/2023 at 3:59 PM, frankendat said:

18 years with a transmission would be fantastic and appropriate, in my mind, as days of banging gears and cooking rubber are long past. Keeping alignment, as precise as possible, I too, believe prudent. 

 

My RL411 transmission [ British  BW M35] is 56 years old and still functional.  Granted I have only 160000 miles on it but automatic transmissions are reliable with preventive maintenance,

 

 

BW 

[datzenmike]

They are and the 3N71B is even better.

 

Heat kills any automatic. If you know you overheated it, (being stuck it happens) basically its fryer oil so change the fluid ASAP. Get an external RV transmission cooler if you don't have one. NEVER tow with an automatic. NEVER overfill !!!

[frankendat]

5 hours ago, MikeRL411 said:

 

My RL411 transmission [ British  BW M35] is 56 years old and still functional.  Granted I have only 160000 miles on it but automatic transmissions are reliable with preventive maintenance,

 

 

BW 

 

4 hours ago, datzenmike said:

They are and the 3N71B is even better.

 

Heat kills any automatic. If you know you overheated it, (being stuck it happens) basically its fryer oil so change the fluid ASAP. Get an external RV transmission cooler if you don't have one. NEVER tow with an automatic. NEVER overfill !!!

I've had an automatic in a couple of life's chapters and they have some +, but for me, their - are more important. Similar to features like remote start and disable, like auto pilot, like Teslas. They could have a parade with every world big brain swearing on a stack of Bibles that the bugs are fixed and millions of miles of incident free operation, I understand they have some +, but for me, their - are more important.

[frankendat]

6 hours ago, bottomwatcher said:

31x10.5s rub slightly with a 2" upper A arm lift, 2 inch body lift and some fender trimming. Going to need more for 32s.

NICE! My unconfirmed unmeasured WAG is skinnier tires will be able to go in the fender and require less lift and/or cutting. But, I am not against cutting or lifts, yours looks great. If the skinny tire fender tuck works, then I'll trade the body lift for a suspension lift

[datzenmike]

27 minutes ago, frankendat said:

 

I've had an automatic in a couple of life's chapters and they have some +, but for me, their - are more important. Similar to features like remote start and disable, like auto pilot, like Teslas. They could have a parade with every world big brain swearing on a stack of Bibles that the bugs are fixed and millions of miles of incident free operation, I understand they have some +, but for me, their - are more important.

 

There aren't too many vehicles today that would benefit from a manual transmission. They are just no fun to drive anyway. My favorite automatic was my 5 year old '69 Charger 318.

[frankendat]

1 hour ago, datzenmike said:

 

There aren't too many vehicles today that would benefit from a manual transmission. They are just no fun to drive anyway. My favorite automatic was my 5 year old '69 Charger 318.

Now see, that is exactly what I am talking about, it is not what would benefit the vehicle, it is what would benefit the driver. I have read of the "new" automatics that give better mpg and power and make you taller, but you unless you can push start it, if necessary, or coast, if necessary, or any other of the benefits that are available with a manual and not overly damaging to the engine. I'll pass.

 

 

[frankendat]

2 hours ago, datzenmike said:

 

There aren't too many vehicles today that would benefit from a manual transmission. They are just no fun to drive anyway. My favorite automatic was my 5 year old '69 Charger 318.

I am being contrary. When my DD was a '78 Coup'deville, (automatic) that car would glide and demanded to be driven with the power seat leaned back and one hand on the wheel.

[datzenmike]

Would rowing through a 6 speed SUV make the experience better? Can't see it. When driving my wife's Toyota Rav 4 I sigh, sit back and just wait till I get where I point it. There is zero interest in the ride, it's like sitting at home on the couch watching a movie you've seen a dozen times. Compare this to a vehicle that you actually want to be in, be seen in, a vehicle that entertains you as you drive, one that involves you in it's running as you make it do a few tricks for your enjoyment..... and make a little noise.

[frankendat]

Your point is well taken. My parents gave in and now rent, I mean "lease" their DD. As long as they follow the rules, maintenance and problems are covered. I thought it was age, but now think it is finances, with a splash of F*** the Man, that propels my vehicle angst.

I like the same drive, as driven many times before, because it is not always the same. Maybe the truck worked a little harder on that last hill or picked up a new vibration, catching problems early saves cash and something off might inspire carpooling, until the weekend, when I can give a look.

I am forbidden by warranty and by wife from working on her "newish" (4-year-old) ride. A road trip with her sister last week. They broke down called insurance covered roadside assist, (included with insurance) car towed to the closest town, because of insurance, price was in the 000 instead of 0000 –tow, new fuel pump and install + night in hotel = over 2k

Snags like this sting.

A decade or two back we had a similar situation with my wife's '88 Dakota pickup. Truck broke down, I was called. Not fuel getting to carb, I check filters, check lines for flow (by blowing), have her crank it - no fuel = fuel pump. New pump $100 in nearest town. To get to the fuel pump the bed had to come off (asshole engineers) I took a battery operated grinder and sawzall, cut a 10x10 square out of the bed above the gas tank (Yes sparks, it was an engaging endeavor) in the dry field where I pushed the truck, off the highway. Most of this work was performed by mouth held or wife held flashlight (no headband LED’s, no hotel). Truck drove home, when we sold that truck, years later, it still had a hole in the bed. I never got around to fixing it. Total out of pocket, less than $500.

My antidote hits on many of my problems with new America and when I started writing it, that wasn't my intention. Even though, the recent fuel pump problem was addressed without issue, I prefer the earlier replacement, because of the lack of control, afforded by the recent. Once you are no longer in control you are at the mercy of others, of strangers, which is fine, until it isn't, or the check comes due. History tells us, every single time, too much control is seceded, suffering, destruction and death follow. How much is too much?

[datzenmike]

521, 510, B210 620 710s are all the Datsuns I have owned since the mid '70s. None were ever in a garage for repairs, I did every bit of wrenching myself. Had a head machined and tires balanced I couldn't do that at home. My 620 and both 710 had sets of tires put on by hand. My wife's leased Rav 4 I have never even seen the engine. Don't even know if you can even check the oil or not and do not care.