Quick question

I have an 88 Cherokee (4.0, BA10/5) and I can't find a sticker for the
correct fuel octane.

I've been using 87 octane in it but I wonder if that's correct.

Thanks!

Budd

Budd Cochran wrote:
> I have an 88 Cherokee (4.0, BA10/5) and I can't find a sticker for the
> correct fuel octane.
>
> I've been using 87 octane in it but I wonder if that's correct.
>
> Thanks!
>
> Budd
>
>

It could be in the owner's manual.

Unless you have 10:1 or greater compression, you don't need high octane gas.

"Scott in Baltimore" > wrote in message
...
> Budd Cochran wrote:
>> I have an 88 Cherokee (4.0, BA10/5) and I can't find a sticker for the
>> correct fuel octane.
>>
>> I've been using 87 octane in it but I wonder if that's correct.
>>
>> Thanks!
>>
>> Budd
>
> It could be in the owner's manual.
>
> Unless you have 10:1 or greater compression, you don't need high octane
> gas.

Bought the XJ very used (330,000+ miles) ... no manual.

And I've been a mechanic, heavy equipment and small engine, so I do
understand that I don't need higher octane than recommended ...

and that's why I asked.

I just thought someone here might know but I'll just search for a manual on
the 'net.

Budd

Budd Cochran wrote:

> I have an 88 Cherokee (4.0, BA10/5) and I can't find a sticker for the
> correct fuel octane.
>
> I've been using 87 octane in it but I wonder if that's correct.

The manual (and compression both new and as read) for my 88 MJ indicate that
87 is acceptable. In the 100k miles I've put on it, it has never seen
anything higher.

--
WHonea

--- Posted via news://freenews.netfront.net/ - Complaints to ---

From my 1997 Jeep book, looking at Cherokee 4.0:

HP net brake @ rpm 190 @ 4600
Tq net lb-ft @ rpm 225 @ 3000
Displacement cc(cu) 3956(242)
Bore & stroke mm 98.4 x 86.7
Bore $ stroke in 3.88 x 3.41
Compression ratio 8.8:1

Will Honea wrote:
> Budd Cochran wrote:
>
>> I have an 88 Cherokee (4.0, BA10/5) and I can't find a sticker for
>> the correct fuel octane.
>>
>> I've been using 87 octane in it but I wonder if that's correct.
>
> The manual (and compression both new and as read) for my 88 MJ
> indicate that 87 is acceptable. In the 100k miles I've put on it, it
> has never seen anything higher.

Depends on altitude.
Use the lowest one that doesn't ping and adjust up if it does.
The biggest issue you might have is with 10% corn-juice blends.
My 82 C-10 chevy handled 10% fairly well, but some makers are more
suceptable than others.

--
DougW

"Will Honea" > wrote in message
...
> Budd Cochran wrote:
>
>> I have an 88 Cherokee (4.0, BA10/5) and I can't find a sticker for the
>> correct fuel octane.
>>
>> I've been using 87 octane in it but I wonder if that's correct.
>
> The manual (and compression both new and as read) for my 88 MJ indicate
> that
> 87 is acceptable. In the 100k miles I've put on it, it has never seen
> anything higher.
>
> --
> WHonea
>
> --- Posted via news://freenews.netfront.net/ - Complaints to
> ---

Thanks, Will.

I use 87 octane and my altitude (5400 feet) actually allows an octane or two
drop so I'm good.

Budd

On 8/6/2011 21:24, Budd Cochran wrote:
> "Will > wrote in message
> ...
>> Budd Cochran wrote:
>>
>>> I have an 88 Cherokee (4.0, BA10/5) and I can't find a sticker for the
>>> correct fuel octane.
>>>
>>> I've been using 87 octane in it but I wonder if that's correct.
>>
>> The manual (and compression both new and as read) for my 88 MJ indicate
>> that
>> 87 is acceptable. In the 100k miles I've put on it, it has never seen
>> anything higher.
>>
>> --
>> WHonea
>>
>> --- Posted via news://freenews.netfront.net/ - Complaints to
>> ---
>
> Thanks, Will.
>
> I use 87 octane and my altitude (5400 feet) actually allows an octane or two
> drop so I'm good.

And it if does ping, take your foot out of it, and add a gallon or so of
the next higher grade. Mine used to ping very slightly on regular at
sea level, but at current altitude of 5-10000 feet it could probably run
peanut butter.

Budd Cochran wrote:

> I use 87 octane and my altitude (5400 feet) actually allows an octane or
> two drop so I'm good.

Sounds right. I was over Cottonwood Pass (12,000+) a couple of weeks back
and noticed no issues - or at least nothing not expected up there. Lots of
mud and snow for July made the beast struggle a bit.

--
WHonea

--- Posted via news://freenews.netfront.net/ - Complaints to ---