Spit Balling LOL

[Nothing Special]

.... it is a little rough starting out uphill so I use the transfer case low range....

.... If you needed to start from a dead stop on a 8% grade you might be in trouble. That’s why I suggested a 4x4 transmission and T-case. It’s not elegant, but it is an affordable solution to a crawl gear for those occasions when you need it.

For what it's worth, "they" say that you can't shift a transfer case between low and high while you are moving. Obviously it's possible, and if you know what you're doing with the clutch and matching gear speeds it doesn't need to be hard on the transfer case. But for "just anybody" reading this, using the transfer case as a granny gear to get started is not recommended.

 

[Ford F834]

For what it's worth, "they" say that you can't shift a transfer case between low and high while you are moving. Obviously it's possible, and if you know what you're doing with the clutch and matching gear speeds it doesn't need to be hard on the transfer case. But for "just anybody" reading this, using the transfer case as a granny gear to get started is not recommended.

You are exactly right, and the faster you are going the less it will want to shift from low range to high range on the fly. It’s worse than non-synchronized first, but neither one go smoothly while rolling. T-case low range can get you out of a jam or get you to a flatter spot to take off in high range though.

 

[Nothing Special]

.... T-case low range can get you out of a jam or get you to a flatter spot to take off in high range though.

And I'm sure you know this but for other's benefit, low range 2WD is great for moving trailers around the yard or driveway too. A lot less clutch slipping (or a lot less throttle with an auto trans) so it's easier to control.

 

[FuzzFace2]

.... T-case low range can get you out of a jam or get you to a flatter spot to take off in high range though.

And I'm sure you know this but for other's benefit, low range 2WD is great for moving trailers around the yard or driveway too. A lot less clutch slipping (or a lot less throttle with an auto trans) so it's easier to control.

All good information.

If I was to add a 4x4 Tcase I would do a full 4x4 swap but don't really need 4x4 down here like up north.

I also would not be towing the trailer all the time so if setup better for not towing would be the way to go with this truck.

I just don't want to run a higher first gear OD trans than what I have now with the T18 2nd gear, I drive it now as a 3 speed.

Dave ----

[FuzzFace2]

All good information.

If I was to add a 4x4 Tcase I would do a full 4x4 swap but don't really need 4x4 down here like up north.

I also would not be towing the trailer all the time so if setup better for not towing would be the way to go with this truck.

I just don't want to run a higher first gear OD trans than what I have now with the T18 2nd gear, I drive it now as a 3 speed.

Dave ----

Gary got me going back to this with his Calculator page http://www.garysgaragemahal.com/calculators.html

and having fun with numbers.

I got to say the speedo & tach are spot on in my truck (300 six / t18 / 2.75 gear) as I have checked the speed with a GPS shortly after I fixed the speedo gears and just yesterday on the way home was able to see the mile posts, cant do that at 2am in the dark! The mileage is also spot on so a few more tank fills and I should have a good idea of MPG. At 70 MPH & 29" tire I run about 2300 RPM.

So with the information given it looks like I will be looking for a M5-R2 from 88 - 91 small block trucks, if I get lucky maybe a ZF but will not hold my breath.

Right now my granny gear is 17.38 (6.32x2.75=17.38) that is to low with out a load.

2nd gear is 8.50 (3.09x2.75=8.495) and is a little to high for my liking.

The M5-R2

first with my 2.75 rear gear would be 10.73 (3.90x2.75=10.725)

That is good for normal driving but with a load is not so good.

With other rear gear numbers:

3.90x3.08=12.01 is better

3.90x3.25=12.675 is better yet but wonder if maybe to low with out a load?

But starting out in 2nd gear, 2.25

3.25x2.25=7.31 is even worst than my T18 of 8.50 is now so no 2nd gear starts unless we go a lot lower in the axle and that defeats the over dive at that point.

So Over Drive what numbers do we get? (RPM @ 70 MPH)

Stock now 1.1x2.75=2.75 (2300 RPM) (RPM @ 65 MPH 1507) (RPM @ 45 MPH 1435)

.80x2.75=2.20 (1784 RPM)

.80x3.08=2.464 (1999 RPM)

.80x3.25=3.60 (2110 RPM)

The thing to keep in mind is this is for a low revving straight six and the numbers I have are

carb: 120hp @ 3000 RPMs / 255tq @ 1400 RPMs

So from what I see the M5-R2 with my 2.75 gear is a good starting place and if I was to do a gear swap a 3.08 would be good for the lower first gear load pulling when needed but not so low to be like the T18's granny and I get a good OD ratio with both the 2.75 & 3.08 where and 3.25 only gets me a little lower than what I have now with the T18 & 2.75.

Also this will not pull the trailer all the time, it is a back up when needed and so far in the almost 5 years down here I have only used the trailer to bring the 2 trucks home and that was like 6 months after we got here.

Dave ----

[Gary Lewis]

Gary got me going back to this with his Calculator page http://www.garysgaragemahal.com/calculators.html

and having fun with numbers.

I got to say the speedo & tach are spot on in my truck (300 six / t18 / 2.75 gear) as I have checked the speed with a GPS shortly after I fixed the speedo gears and just yesterday on the way home was able to see the mile posts, cant do that at 2am in the dark! The mileage is also spot on so a few more tank fills and I should have a good idea of MPG. At 70 MPH & 29" tire I run about 2300 RPM.

So with the information given it looks like I will be looking for a M5-R2 from 88 - 91 small block trucks, if I get lucky maybe a ZF but will not hold my breath.

Right now my granny gear is 17.38 (6.32x2.75=17.38) that is to low with out a load.

2nd gear is 8.50 (3.09x2.75=8.495) and is a little to high for my liking.

The M5-R2

first with my 2.75 rear gear would be 10.73 (3.90x2.75=10.725)

That is good for normal driving but with a load is not so good.

With other rear gear numbers:

3.90x3.08=12.01 is better

3.90x3.25=12.675 is better yet but wonder if maybe to low with out a load?

But starting out in 2nd gear, 2.25

3.25x2.25=7.31 is even worst than my T18 of 8.50 is now so no 2nd gear starts unless we go a lot lower in the axle and that defeats the over dive at that point.

So Over Drive what numbers do we get? (RPM @ 70 MPH)

Stock now 1.1x2.75=2.75 (2300 RPM) (RPM @ 65 MPH 1507) (RPM @ 45 MPH 1435)

.80x2.75=2.20 (1784 RPM)

.80x3.08=2.464 (1999 RPM)

.80x3.25=3.60 (2110 RPM)

The thing to keep in mind is this is for a low revving straight six and the numbers I have are

carb: 120hp @ 3000 RPMs / 255tq @ 1400 RPMs

So from what I see the M5-R2 with my 2.75 gear is a good starting place and if I was to do a gear swap a 3.08 would be good for the lower first gear load pulling when needed but not so low to be like the T18's granny and I get a good OD ratio with both the 2.75 & 3.08 where and 3.25 only gets me a little lower than what I have now with the T18 & 2.75.

Also this will not pull the trailer all the time, it is a back up when needed and so far in the almost 5 years down here I have only used the trailer to bring the 2 trucks home and that was like 6 months after we got here.

Dave ----

Dave - Later today I'll see if I can put the new section in the Calculators page. Maybe that will help you make your decision?

[FuzzFace2]

Dave - Later today I'll see if I can put the new section in the Calculators page. Maybe that will help you make your decision?

No rush for me as it will be sometime before I will do this swap and based on what has been posted looking for a small block ZF is like the needle in the hay stack and the M5 does not look all that bad when I ran the (total or final) numbers for the gear ratios.

Dave ----

 

[Rembrant]

So from what I see the M5-R2 with my 2.75 gear is a good starting place and if I was to do a gear swap a 3.08 would be good for the lower first gear load pulling when needed but not so low to be like the T18's granny and I get a good OD ratio with both the 2.75 & 3.08 where and 3.25 only gets me a little lower than what I have now with the T18 & 2.75.

Dave,

I'm running the M5-R2 with 3.08 gears, but my tires are lower profile...I believe 28" OD. I find it geared a tiny bit on a tall side, but it's perfectly fine for what I do with the truck. I don't haul anything, and the little 302 is built up a little bit. I think it's right around 2000 RPM at 65-70 MPH...I don't remember exactly where it was.

I really like the trans, and I'm hoping for some good MPG numbers when I can finally get testing it again in the spring. I bought a spare trans a while back...it was local-ish and cheap-ish (at $150) so I grabbed it. It's pretty grungy looking, but it was my plan to rebuild it when I run out of other rehab projects.

 

[Gary Lewis]

Dave - Later today I'll see if I can put the new section in the Calculators page. Maybe that will help you make your decision?

No rush for me as it will be sometime before I will do this swap and based on what has been posted looking for a small block ZF is like the needle in the hay stack and the M5 does not look all that bad when I ran the (total or final) numbers for the gear ratios.

Dave ----

Go check it out. Is that what you were looking for? If not, what did I miss? http://www.garysgaragemahal.com/calculators.html

[FuzzFace2]

So from what I see the M5-R2 with my 2.75 gear is a good starting place and if I was to do a gear swap a 3.08 would be good for the lower first gear load pulling when needed but not so low to be like the T18's granny and I get a good OD ratio with both the 2.75 & 3.08 where and 3.25 only gets me a little lower than what I have now with the T18 & 2.75.

Dave,

I'm running the M5-R2 with 3.08 gears, but my tires are lower profile...I believe 28" OD. I find it geared a tiny bit on a tall side, but it's perfectly fine for what I do with the truck. I don't haul anything, and the little 302 is built up a little bit. I think it's right around 2000 RPM at 65-70 MPH...I don't remember exactly where it was.

I really like the trans, and I'm hoping for some good MPG numbers when I can finally get testing it again in the spring. I bought a spare trans a while back...it was local-ish and cheap-ish (at $150) so I grabbed it. It's pretty grungy looking, but it was my plan to rebuild it when I run out of other rehab projects.

Cory I was hopping you would see this and I remember you saying your setup was geared a little high.

I was also thinking you have a 302 that is a higher revving motor for the HP & TQ than my stock low revving 300 and then you built it up and that would make it a little higher still.

Would you know, of course you know, what your 302's HP & TQ is at what RPM's?

I would like to see how it compares to a stock 300 as that can tell how well the 300 will like a M5-R2 transmission.

BTW I don't remember did you do the trany swap before or after the built up motor?

Dave ----