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Grandsons Truck T5

Posted: September 7, 2017, 9:29 am
by 64 f100
As I said I finally got the truck started and running and chasing down a few problems. I drove it around the block with the 3.73 gears, and I find it to be like a granny four speed in low gear with the gears that are in the rear end. Have to shift very quickly. I see no advantage to having to shift that quick, and am wondering what gear ratio would help improve this, possibly 3.25 or 3.00. Any comments?

Re: Grandsons Truck T5

Posted: September 7, 2017, 10:06 am
by aj64f100390-292
I still need to double check my rear end ratio but My 64 f100 with a fresh 292 y block, and BW T98 4spd , with what I'm pretty sure is 3.25 rear gears. I shift from 2nd to 3rd at 10-15 just cruising around not speed shifting, and 3rd to 4th @ 27-30 mph just cruising around not speed shifting. and at 50 MPH my rpms are right below 2100 RPM however it is still running to rich for me to tell you mpgs..need a tune kit for the edelbrock..but I'm not sure that's what you were asking so back to the ratios. 3.00, 2.73s or higher you would probably have to take off in granny...but the rule of thumb is that the higher the gears the lower you rpms @ hwy speed, the more mpg you can squeeze out of it...but there is a happy medium you should shoot for.. but then you get into whether you should decide on swapping a OD transmission... How ever I've read a lot of post online lately with guys with y blocks getting 18-20 mpg with 3,00s..one guy with a 64 f100 292 claimed that...but I'm still not so sure that's all that true..who's to say he was accurate..But don't get me wrong I would LOVE to get 20 hwy MPG so I hope he is right 8). But Ill probebly end up going with an od tranny..but with my budget I may have to get a non granny truck 5 spd od myself..want to get an nv4500 5spd od or nv5600 6 spd od both have granny but they are pretty pricey right now..

Re: Grandsons Truck T5

Posted: September 7, 2017, 10:07 am
by aj64f100390-292
wait the title says t5 did you Install a t5?

Re: Grandsons Truck T5

Posted: September 7, 2017, 11:18 am
by unibody madness
Ok What motor are you running?
My stock built 292/3.50 rear chunk, driven by wc T5 with .68 od gear runs right at 2100 rpm doing 70, steep hills will make me down shift to fourth depending on initial speed,severity or duration of hill... not sure if a 223 will be able to ever pull 5th gear without 4.11 gears
I would love 3.00 or 2.75 rear chunk for the 460 however.

Re: Grandsons Truck T5

Posted: September 7, 2017, 7:32 pm
by 64 f100
I'm running an early world class T5 behind a 351W with Aluminum X3O7 high port heads and an RPM air gap intake ported to the heads, a mild torque cam, and Sanderson block header style headers. The block now has 4 bolt mains and is a 59 block. Compressions should be about 9.5 to 1 and it is bored 30 over. What I'm saying is that with the 3.73 gears it's almost like running a granny 4 speed, in that you have to shift it to soon coming out of first. You just barely start to move before you need to shift. I will leave the gears alone for now but will change those when it has the bed on it and it is ready for the road. Need to play with it on the road before I make a decision. When I change gears it will get a traclok.

Re: Grandsons Truck T5

Posted: September 7, 2017, 8:57 pm
by unibody madness
Sounds cool, if I might suggest spending the money on a good shifter with positive stops. I try not to over drive mine but I used the original tall shifter from the t98 and bent my first gear shifting fork with no problem.

Re: Grandsons Truck T5

Posted: September 8, 2017, 9:32 am
by 64 f100
Shifter has positive stops, but is not an expensive unit. I went thru this transmission and hopefully it will survive. Since it is an early 86/7 model tranny, it is not rated for the HP. this motor will produce, roughly 400hp. Shifts like butter at the moment.

Re: Grandsons Truck T5

Posted: September 8, 2017, 3:45 pm
by charliemccraney
Worldclass T5 doesn't tell us a whole lot. A V8 T5 will have a taller 1st gear than a 4 cyl T5. If you have a 4 cyl T5, then it could be more of a granny like 1st gear, though still quite a ways away from a granny gear. There should be a tag on the transmission. That will help to identify it.

Another thing to consider is that the a rear gear change will affect every gear, not 1st gear alone, so if you are happy with the way it drives in 2nd - 5th, then a rear gear change is not wise.

If it turns out to be a V8 T5, then I think it is some mechanical issue, slipping clutch, or slipping tires ;) for instance or perception like keeping the RPM lower than it needs to be for some reason.

I have a V8 T5 with 2.95 1st gear and a 3.70 rear gear and it does not at all feel like a granny gear.

Re: Grandsons Truck T5

Posted: September 8, 2017, 8:32 pm
by unibody madness
my t5 is the 1352-165... it has 3.15 R 3.35 1st 1.93 2nd 1.29 3rd 1.00 4th and .68 5th and I am running 3.50 rear gears and although I am running short tires on 15 " rims the gears do seem a little close

Re: Grandsons Truck T5

Posted: October 7, 2017, 10:02 am
by 64 f100
Finally got around to getting the numbers off the transmission, so here these are.
E6ZA?R 7005 FB REP ATI
13-52-169 67805 CO872
Can anyone ID exactly what this originally fit?
Thanks,
Rich

Re: Grandsons Truck T5

Posted: October 7, 2017, 12:14 pm
by charliemccraney

Re: Grandsons Truck T5

Posted: October 7, 2017, 12:48 pm
by unibody madness
Just checked my tag number again, is as Charlie stated, the 13-52 169 and the 13-52 165 have the same gear ratios, the 165 is in another truck.
I believe you would be happier with a 3.00 or 2.75 since you have the power to pull those gears in fifth.
Your plan to drive it some in all gears freeway ect. makes a bunch of sense

Re: Grandsons Truck T5

Posted: October 9, 2017, 8:26 am
by 64 f100
Have never checked to see what ratio the Mustangs came with in the rear end, but figured it must be something like 3.25 or 3.00. . I will be putting a posi in it when I change the ratio, but want something drivable but may have to get different speedo gear or some kind of reducer to make speed show right. Thanks for the input from everybody. Still trying t o find the noise in the engine.

Re: Grandsons Truck T5

Posted: October 9, 2017, 3:30 pm
by charliemccraney
You definitely will need a different speedo gear.

You also have to be careful comparing only rear end ratios between totally different vehicles. The truck very likely has much larger diameter tires than the Mustang, which will have the effect of making the truck be taller, everything else being equal. So for instance, some hypothetical numbers, a truck with 28" tires would need a 3.45 ratio rear end in order to actually work out the same as another vehicle with 26" tires and a 3.20.